25643955 has 16 divisors (see below), whose sum is σ = 41094144. Its totient is φ = 13655520.

The previous prime is 25643921. The next prime is 25643957. The reversal of 25643955 is 55934652.

It is not a de Polignac number, because 25643955 - 2⁸ = 25643699 is a prime.

It is a super-2 number, since 2×25643955² = 1315224856084050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (25643957) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15582 + ... + 17148.

It is an arithmetic number, because the mean of its divisors is an integer number (2568384).

Almost surely, 2^25643955 is an apocalyptic number.

25643955 is a deficient number, since it is larger than the sum of its proper divisors (15450189).

25643955 is a wasteful number, since it uses less digits than its factorization.

25643955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2666.

The product of its digits is 162000, while the sum is 39.

The square root of 25643955 is about 5063.9860781799. The cubic root of 25643955 is about 294.8911021979.

The spelling of 25643955 in words is "twenty-five million, six hundred forty-three thousand, nine hundred fifty-five".