25640511402 has 32 divisors (see below), whose sum is σ = 56998468800. Its totient is φ = 7623249920.

The previous prime is 25640511397. The next prime is 25640511427. The reversal of 25640511402 is 20411504652.

It is a self number, because there is not a number n which added to its sum of digits gives 25640511402.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3661527 + ... + 3668522.

It is an arithmetic number, because the mean of its divisors is an integer number (1781202150).

Almost surely, 2^25640511402 is an apocalyptic number.

25640511402 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

25640511402 is an abundant number, since it is smaller than the sum of its proper divisors (31357957398).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

25640511402 is a wasteful number, since it uses less digits than its factorization.

25640511402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7330118.

The product of its (nonzero) digits is 9600, while the sum is 30.

The spelling of 25640511402 in words is "twenty-five billion, six hundred forty million, five hundred eleven thousand, four hundred two".