25523661 has 4 divisors (see below), whose sum is σ = 34031552. Its totient is φ = 17015772.

The previous prime is 25523651. The next prime is 25523711. The reversal of 25523661 is 16632552.

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 not a de Polignac number, because 25523661 - 2⁹ = 25523149 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 (25523621) 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, 4253941 + ... + 4253946.

It is an arithmetic number, because the mean of its divisors is an integer number (8507888).

Almost surely, 2^25523661 is an apocalyptic number.

It is an amenable number.

25523661 is a deficient number, since it is larger than the sum of its proper divisors (8507891).

25523661 is an equidigital number, since it uses as much as digits as its factorization.

25523661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8507890.

The product of its digits is 10800, while the sum is 30.

The square root of 25523661 is about 5052.0947140765. The cubic root of 25523661 is about 294.4292747957.

The spelling of 25523661 in words is "twenty-five million, five hundred twenty-three thousand, six hundred sixty-one".