25601621 has 4 divisors (see below), whose sum is σ = 25611744. Its totient is φ = 25591500.

The previous prime is 25601603. The next prime is 25601623. The reversal of 25601621 is 12610652.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 25601621 - 2²² = 21407317 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25601623) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2366 + ... + 7536.

It is an arithmetic number, because the mean of its divisors is an integer number (6402936).

Almost surely, 2^25601621 is an apocalyptic number.

It is an amenable number.

25601621 is a deficient number, since it is larger than the sum of its proper divisors (10123).

25601621 is an equidigital number, since it uses as much as digits as its factorization.

25601621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10122.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 25601621 is about 5059.8044428614. The cubic root of 25601621 is about 294.7287404006.

The spelling of 25601621 in words is "twenty-five million, six hundred one thousand, six hundred twenty-one".