20625 has 20 divisors (see below), whose sum is σ = 37488. Its totient is φ = 10000.

The previous prime is 20611. The next prime is 20627. The reversal of 20625 is 52602.

It is not a de Polignac number, because 20625 - 2⁵ = 20593 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a nialpdrome in base 14.

It is a zygodrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (20627) by changing a digit.

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 19 ways as a sum of consecutive naturals, for example, 1870 + ... + 1880.

2²⁰⁶²⁵ is an apocalyptic number.

20625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20625 is a deficient number, since it is larger than the sum of its proper divisors (16863).

20625 is an equidigital number, since it uses as much as digits as its factorization.

20625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34 (or 19 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 15.

The square root of 20625 is about 143.6140661635. The cubic root of 20625 is about 27.4240327622.

It can be divided in two parts, 206 and 25, that added together give a triangular number (231 = T₂₁).

The spelling of 20625 in words is "twenty thousand, six hundred twenty-five".