25905921 has 16 divisors (see below), whose sum is σ = 35112000. Its totient is φ = 16987968.

The previous prime is 25905899. The next prime is 25905941. The reversal of 25905921 is 12950952.

It is not a de Polignac number, because 25905921 - 2²¹ = 23808769 is a prime.

It is a super-2 number, since 2×25905921² = 1342233485716482, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (25905941) 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, 74055 + ... + 74403.

It is an arithmetic number, because the mean of its divisors is an integer number (2194500).

Almost surely, 2^25905921 is an apocalyptic number.

It is an amenable number.

25905921 is a deficient number, since it is larger than the sum of its proper divisors (9206079).

25905921 is a wasteful number, since it uses less digits than its factorization.

25905921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 688.

The product of its (nonzero) digits is 8100, while the sum is 33.

The square root of 25905921 is about 5089.7859483479. The cubic root of 25905921 is about 295.8918561908.

The spelling of 25905921 in words is "twenty-five million, nine hundred five thousand, nine hundred twenty-one".