21507962983 has 12 divisors (see below), whose sum is σ = 23741161864. Its totient is φ = 19369252800.

The previous prime is 21507962963. The next prime is 21507963011. The reversal of 21507962983 is 38926970512.

It is a de Polignac number, because none of the positive numbers 2^k-21507962983 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21507962983.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21507962933) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 470253 + ... + 513958.

Almost surely, 2^21507962983 is an apocalyptic number.

21507962983 is a deficient number, since it is larger than the sum of its proper divisors (2233198881).

21507962983 is an equidigital number, since it uses as much as digits as its factorization.

21507962983 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 984306 (or 984265 counting only the distinct ones).

The product of its (nonzero) digits is 1632960, while the sum is 52.

The spelling of 21507962983 in words is "twenty-one billion, five hundred seven million, nine hundred sixty-two thousand, nine hundred eighty-three".