625 can be written using four 4's:
See also 113
625 has 5
divisors (see below), whose sum is σ = 781
Its totient is φ = 500
The previous prime is 619. The next prime is 631. The reversal of 625 is 526.
625 = T24 + T25.
The square root of 625 is 25.
It is a perfect power (a square, a biquadrate), and thus also a powerful number.
625 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.
It is an interprime number because it is at equal distance from previous prime (619) and next prime (631).
It can be written as a sum of positive squares in 2 ways, for example, as 49 + 576 = 7^2 + 24^2
It is a tau number, because it is divible by the number of its divisors (5).
It is an automorphic number since its square, 390625, ends in 625.
It is a trimorphic number since its cube, 244140625, ends in 625.
It is not a de Polignac number, because 625 - 23 = 617 is a prime.
It is a magnanimous number.
It is a Duffinian number.
Its product of digits (60) is a multiple of the sum of its prime divisors (5).
It is a nialpdrome in base 5, base 9 and base 12.
It is an unprimeable number.
It is a pernicious number, because its binary representation contains a prime number (5) of ones.
It is a polite number, since it can be written in 4 ways as a sum of consecutive naturals, for example, 123 + ... + 127.
625 is a Friedman number, since it can be written as 5^(6-2), using all its digits and the basic arithmetic operations.
625 is the 25-th square number.
625 is the 13-th centered octagonal number.
It is an amenable number.
625 is a deficient number, since it is larger than the sum of its proper divisors (156).
625 is an frugal number, since it uses more digits than its factorization.
625 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 20 (or 5 counting only the distinct ones).
The product of its digits is 60, while the sum is 13.
The cubic root of 625 is about 8.5498797334.
Subtracting from 625 its product of digits (60), we obtain a palindrome (565).
Subtracting from 625 its reverse (526), we obtain a palindrome (99).
The spelling of 625 in words is "six hundred twenty-five", and thus it is an aban number and an oban number.