25966581 has 4 divisors (see below), whose sum is σ = 34622112. Its totient is φ = 17311052.

The previous prime is 25966553. The next prime is 25966583. The reversal of 25966581 is 18566952.

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 25966581 - 2⁹ = 25966069 is a prime.

It is a super-2 number, since 2×25966581² = 1348526657659122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25966583) 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, 4327761 + ... + 4327766.

It is an arithmetic number, because the mean of its divisors is an integer number (8655528).

Almost surely, 2^25966581 is an apocalyptic number.

It is an amenable number.

25966581 is a deficient number, since it is larger than the sum of its proper divisors (8655531).

25966581 is an equidigital number, since it uses as much as digits as its factorization.

25966581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8655530.

The product of its digits is 129600, while the sum is 42.

The square root of 25966581 is about 5095.7414573347. The cubic root of 25966581 is about 296.1226246556.

The spelling of 25966581 in words is "twenty-five million, nine hundred sixty-six thousand, five hundred eighty-one".