25565791405 has 64 divisors (see below), whose sum is σ = 39390912000. Its totient is φ = 15789634560.

The previous prime is 25565791337. The next prime is 25565791421. The reversal of 25565791405 is 50419756552.

It is not a de Polignac number, because 25565791405 - 2⁹ = 25565790893 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2050069 + ... + 2062501.

It is an arithmetic number, because the mean of its divisors is an integer number (615483000).

Almost surely, 2^25565791405 is an apocalyptic number.

It is an amenable number.

25565791405 is a deficient number, since it is larger than the sum of its proper divisors (13825120595).

25565791405 is a wasteful number, since it uses less digits than its factorization.

25565791405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12579 (or 12565 counting only the distinct ones).

The product of its (nonzero) digits is 1890000, while the sum is 49.

The spelling of 25565791405 in words is "twenty-five billion, five hundred sixty-five million, seven hundred ninety-one thousand, four hundred five".