25506921 has 24 divisors (see below), whose sum is σ = 38687040. Its totient is φ = 14919520.

The previous prime is 25506907. The next prime is 25506937. The reversal of 25506921 is 12960552.

It is a happy number.

It is not a de Polignac number, because 25506921 - 2¹¹ = 25504873 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (25506121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9316 + ... + 11738.

It is an arithmetic number, because the mean of its divisors is an integer number (1611960).

Almost surely, 2^25506921 is an apocalyptic number.

It is an amenable number.

25506921 is a deficient number, since it is larger than the sum of its proper divisors (13180119).

25506921 is a wasteful number, since it uses less digits than its factorization.

25506921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2477 (or 2466 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 30.

The square root of 25506921 is about 5050.4377038035. The cubic root of 25506921 is about 294.3648923914.

The spelling of 25506921 in words is "twenty-five million, five hundred six thousand, nine hundred twenty-one".