8921621978730 has 24 divisors (see below), whose sum is σ = 23196217144932. Its totient is φ = 2379099194304.

The previous prime is 8921621978719. The next prime is 8921621978761. The reversal of 8921621978730 is 378791261298.

It can be written as a sum of positive squares in 2 ways, for example, as 8910386190729 + 11235788001 = 2985027^2 + 105999^2 .

It is a hoax number, since the sum of its digits (63) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 49564566459 + ... + 49564566638.

Almost surely, 2^{8921621978730} is an apocalyptic number.

8921621978730 is an abundant number, since it is smaller than the sum of its proper divisors (14274595166202).

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

8921621978730 is a wasteful number, since it uses less digits than its factorization.

8921621978730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99129133110 (or 99129133107 counting only the distinct ones).

The product of its (nonzero) digits is 18289152, while the sum is 63.

The spelling of 8921621978730 in words is "eight trillion, nine hundred twenty-one billion, six hundred twenty-one million, nine hundred seventy-eight thousand, seven hundred thirty".