25641557 has 4 divisors (see below), whose sum is σ = 26468736. Its totient is φ = 24814380.

The previous prime is 25641529. The next prime is 25641563. The reversal of 25641557 is 75514652.

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 25641557 - 2¹⁶ = 25576021 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 (25641157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 413543 + ... + 413604.

It is an arithmetic number, because the mean of its divisors is an integer number (6617184).

Almost surely, 2^25641557 is an apocalyptic number.

It is an amenable number.

25641557 is a deficient number, since it is larger than the sum of its proper divisors (827179).

25641557 is an equidigital number, since it uses as much as digits as its factorization.

25641557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 827178.

The product of its digits is 42000, while the sum is 35.

The square root of 25641557 is about 5063.7493026413. The cubic root of 25641557 is about 294.8819100263.

The spelling of 25641557 in words is "twenty-five million, six hundred forty-one thousand, five hundred fifty-seven".