25623661 has 4 divisors (see below), whose sum is σ = 29284192. Its totient is φ = 21963132.

The previous prime is 25623659. The next prime is 25623667. The reversal of 25623661 is 16632652.

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.

It is a cyclic number.

It is not a de Polignac number, because 25623661 - 2¹ = 25623659 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25623667) 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, 1830255 + ... + 1830268.

It is an arithmetic number, because the mean of its divisors is an integer number (7321048).

Almost surely, 2^25623661 is an apocalyptic number.

It is an amenable number.

25623661 is a deficient number, since it is larger than the sum of its proper divisors (3660531).

25623661 is an equidigital number, since it uses as much as digits as its factorization.

25623661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3660530.

The product of its digits is 12960, while the sum is 31.

The square root of 25623661 is about 5061.9819241084. The cubic root of 25623661 is about 294.8132917953.

The spelling of 25623661 in words is "twenty-five million, six hundred twenty-three thousand, six hundred sixty-one".