25421565 has 16 divisors (see below), whose sum is σ = 43803648. Its totient is φ = 12515136.

The previous prime is 25421551. The next prime is 25421569. The reversal of 25421565 is 56512452.

It is not a de Polignac number, because 25421565 - 2⁴ = 25421549 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25421569) 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, 64989 + ... + 65378.

It is an arithmetic number, because the mean of its divisors is an integer number (2737728).

Almost surely, 2^25421565 is an apocalyptic number.

It is an amenable number.

25421565 is a deficient number, since it is larger than the sum of its proper divisors (18382083).

25421565 is a wasteful number, since it uses less digits than its factorization.

25421565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130388.

The product of its digits is 12000, while the sum is 30.

The square root of 25421565 is about 5041.9802657289. The cubic root of 25421565 is about 294.0361726051.

The spelling of 25421565 in words is "twenty-five million, four hundred twenty-one thousand, five hundred sixty-five".