25164561 has 4 divisors (see below), whose sum is σ = 33552752. Its totient is φ = 16776372.

The previous prime is 25164533. The next prime is 25164563. The reversal of 25164561 is 16546152.

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 25164561 - 2²¹ = 23067409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25164563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4194091 + ... + 4194096.

It is an arithmetic number, because the mean of its divisors is an integer number (8388188).

Almost surely, 2^25164561 is an apocalyptic number.

It is an amenable number.

25164561 is a deficient number, since it is larger than the sum of its proper divisors (8388191).

25164561 is an equidigital number, since it uses as much as digits as its factorization.

25164561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8388190.

The product of its digits is 7200, while the sum is 30.

The square root of 25164561 is about 5016.4291084396. The cubic root of 25164561 is about 293.0419436201.

The spelling of 25164561 in words is "twenty-five million, one hundred sixty-four thousand, five hundred sixty-one".