20487991012 has 12 divisors (see below), whose sum is σ = 35976354876. Its totient is φ = 10209032480.

The previous prime is 20487990973. The next prime is 20487991033. The reversal of 20487991012 is 21019978402.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 14223901696 + 6264089316 = 119264^2 + 79146^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20487991012.

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 3 ways as a sum of consecutive naturals, for example, 8739439 + ... + 8741782.

It is an arithmetic number, because the mean of its divisors is an integer number (2998029573).

Almost surely, 2^20487991012 is an apocalyptic number.

It is an amenable number.

20487991012 is a deficient number, since it is larger than the sum of its proper divisors (15488363864).

20487991012 is a wasteful number, since it uses less digits than its factorization.

20487991012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17481518 (or 17481516 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 43.

The spelling of 20487991012 in words is "twenty billion, four hundred eighty-seven million, nine hundred ninety-one thousand, twelve".