20625641540 has 36 divisors (see below), whose sum is σ = 50385498156. Its totient is φ = 7071648192.

The previous prime is 20625641497. The next prime is 20625641567. The reversal of 20625641540 is 4514652602.

It can be written as a sum of positive squares in 2 ways, for example, as 8895885124 + 11729756416 = 94318^2 + 108304^2 .

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 20625641540.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10522307 + ... + 10524266.

It is an arithmetic number, because the mean of its divisors is an integer number (1399597171).

Almost surely, 2^20625641540 is an apocalyptic number.

20625641540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20625641540 is an abundant number, since it is smaller than the sum of its proper divisors (29759856616).

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

20625641540 is a wasteful number, since it uses less digits than its factorization.

20625641540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21046596 (or 21046587 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 35.

The spelling of 20625641540 in words is "twenty billion, six hundred twenty-five million, six hundred forty-one thousand, five hundred forty".