25657013405 has 4 divisors (see below), whose sum is σ = 30788416092. Its totient is φ = 20525610720.

The previous prime is 25657013399. The next prime is 25657013407. The reversal of 25657013405 is 50431075652.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 3705035161 + 21951978244 = 60869^2 + 148162^2 .

It is a de Polignac number, because none of the positive numbers 2^k-25657013405 is a prime.

It is a super-4 number, since 4×25657013405⁴ (a number of 43 digits) contains 4444 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 (25657013407) 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, 2565701336 + ... + 2565701345.

It is an arithmetic number, because the mean of its divisors is an integer number (7697104023).

Almost surely, 2^25657013405 is an apocalyptic number.

It is an amenable number.

25657013405 is a deficient number, since it is larger than the sum of its proper divisors (5131402687).

25657013405 is an equidigital number, since it uses as much as digits as its factorization.

25657013405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5131402686.

The product of its (nonzero) digits is 126000, while the sum is 38.

The spelling of 25657013405 in words is "twenty-five billion, six hundred fifty-seven million, thirteen thousand, four hundred five".