25660861 has 4 divisors (see below), whose sum is σ = 25970112. Its totient is φ = 25351612.

The previous prime is 25660829. The next prime is 25660883. The reversal of 25660861 is 16806652.

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 25660861 - 2⁵ = 25660829 is a prime.

It is a super-2 number, since 2×25660861² = 1316959574522642, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25670861) 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, 154501 + ... + 154666.

It is an arithmetic number, because the mean of its divisors is an integer number (6492528).

Almost surely, 2^25660861 is an apocalyptic number.

It is an amenable number.

25660861 is a deficient number, since it is larger than the sum of its proper divisors (309251).

25660861 is an equidigital number, since it uses as much as digits as its factorization.

25660861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309250.

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 25660861 is about 5065.6550415519. The cubic root of 25660861 is about 294.9558911356.

The spelling of 25660861 in words is "twenty-five million, six hundred sixty thousand, eight hundred sixty-one".