257720625 has 30 divisors (see below), whose sum is σ = 465190154.
Its totient is φ = 137448000.
The previous prime is 257720621. The next prime is 257720627. The reversal of 257720625 is 526027752.
257720625 is a `hidden beast` number, since 2 + 5 + 7 + 7 + 20 + 625 = 666.
It can be written as a sum of positive squares in 5 ways, for example, as 49322529 + 208398096 = 7023^2 + 14436^2
It is not a de Polignac number, because 257720625 - 22 = 257720621 is a prime.
It is a Duffinian number.
It is a self number, because there is not a number n which added to its sum of digits gives 257720625.
It is not an unprimeable number, because it can be changed into a prime (257720621) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (13) of ones.
It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 17284 + ... + 28533.
Almost surely, 2257720625 is an apocalyptic number.
257720625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.
It is an amenable number.
257720625 is a deficient number, since it is larger than the sum of its proper divisors (207469529).
257720625 is an equidigital number, since it uses as much as digits as its factorization.
257720625 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 45843 (or 45825 counting only the distinct ones).
The product of its (nonzero) digits is 58800, while the sum is 36.
The square root of 257720625 is about 16053.6794847786.
The cubic root of 257720625 is about 636.3798090355.
The spelling of 257720625 in words is "two hundred fifty-seven million, seven hundred twenty thousand, six hundred twenty-five".