25642387 has 4 divisors (see below), whose sum is σ = 26062816. Its totient is φ = 25221960.

The previous prime is 25642327. The next prime is 25642399. The reversal of 25642387 is 78324652.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 25642387 - 2¹¹ = 25640339 is a prime.

It is a super-2 number, since 2×25642387² = 1315064022115538, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25642327) 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, 210123 + ... + 210244.

It is an arithmetic number, because the mean of its divisors is an integer number (6515704).

Almost surely, 2^25642387 is an apocalyptic number.

25642387 is a deficient number, since it is larger than the sum of its proper divisors (420429).

25642387 is an equidigital number, since it uses as much as digits as its factorization.

25642387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420428.

The product of its digits is 80640, while the sum is 37.

The square root of 25642387 is about 5063.8312570622. The cubic root of 25642387 is about 294.8850917018.

The spelling of 25642387 in words is "twenty-five million, six hundred forty-two thousand, three hundred eighty-seven".