25640084020 has 12 divisors (see below), whose sum is σ = 53844176484. Its totient is φ = 10256033600.

The previous prime is 25640083999. The next prime is 25640084039. The reversal of 25640084020 is 2048004652.

It can be written as a sum of positive squares in 2 ways, for example, as 7805015716 + 17835068304 = 88346^2 + 133548^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 641002081 + ... + 641002120.

It is an arithmetic number, because the mean of its divisors is an integer number (4487014707).

Almost surely, 2^25640084020 is an apocalyptic number.

25640084020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25640084020 is an abundant number, since it is smaller than the sum of its proper divisors (28204092464).

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

25640084020 is a wasteful number, since it uses less digits than its factorization.

25640084020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1282004210 (or 1282004208 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 31.

Adding to 25640084020 its reverse (2048004652), we get a palindrome (27688088672).

The spelling of 25640084020 in words is "twenty-five billion, six hundred forty million, eighty-four thousand, twenty".