25656431 has 4 divisors (see below), whose sum is σ = 26771952. Its totient is φ = 24540912.

The previous prime is 25656409. The next prime is 25656443. The reversal of 25656431 is 13465652.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25656431 is a prime.

It is a super-2 number, since 2×25656431² = 1316504903315522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25656131) 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, 557726 + ... + 557771.

It is an arithmetic number, because the mean of its divisors is an integer number (6692988).

Almost surely, 2^25656431 is an apocalyptic number.

25656431 is a deficient number, since it is larger than the sum of its proper divisors (1115521).

25656431 is a wasteful number, since it uses less digits than its factorization.

25656431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1115520.

The product of its digits is 21600, while the sum is 32.

The square root of 25656431 is about 5065.2177643217. The cubic root of 25656431 is about 294.9389167793.

The spelling of 25656431 in words is "twenty-five million, six hundred fifty-six thousand, four hundred thirty-one".