21002309994 has 32 divisors (see below), whose sum is σ = 43465720320. Its totient is φ = 6757394112.

The previous prime is 21002309989. The next prime is 21002310011. The reversal of 21002309994 is 49990320012.

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, 654759 + ... + 686085.

It is an arithmetic number, because the mean of its divisors is an integer number (1358303760).

Almost surely, 2^21002309994 is an apocalyptic number.

21002309994 is an abundant number, since it is smaller than the sum of its proper divisors (22463410326).

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

21002309994 is a wasteful number, since it uses less digits than its factorization.

21002309994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35214.

The product of its (nonzero) digits is 34992, while the sum is 39.

The spelling of 21002309994 in words is "twenty-one billion, two million, three hundred nine thousand, nine hundred ninety-four".