25725021 has 16 divisors (see below), whose sum is σ = 39283200. Its totient is φ = 14668848.

The previous prime is 25725019. The next prime is 25725043. The reversal of 25725021 is 12052752.

It is not a de Polignac number, because 25725021 - 2¹ = 25725019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 25724982 and 25725000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25724021) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12010 + ... + 13988.

It is an arithmetic number, because the mean of its divisors is an integer number (2455200).

Almost surely, 2^25725021 is an apocalyptic number.

25725021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

25725021 is a deficient number, since it is larger than the sum of its proper divisors (13558179).

25725021 is a wasteful number, since it uses less digits than its factorization.

25725021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2608.

The product of its (nonzero) digits is 1400, while the sum is 24.

The square root of 25725021 is about 5071.9839313626. The cubic root of 25725021 is about 295.2015131825.

Adding to 25725021 its reverse (12052752), we get a palindrome (37777773).

The spelling of 25725021 in words is "twenty-five million, seven hundred twenty-five thousand, twenty-one".