21389766763155 has 16 divisors (see below), whose sum is σ = 39112716367104. Its totient is φ = 9778179091680.

The previous prime is 21389766763147. The next prime is 21389766763193. The reversal of 21389766763155 is 55136766798312.

It is not a de Polignac number, because 21389766763155 - 2³ = 21389766763147 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21389766763155.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 101856032101 + ... + 101856032310.

It is an arithmetic number, because the mean of its divisors is an integer number (2444544772944).

Almost surely, 2^{21389766763155} is an apocalyptic number.

21389766763155 is a deficient number, since it is larger than the sum of its proper divisors (17722949603949).

21389766763155 is a wasteful number, since it uses less digits than its factorization.

21389766763155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 203712064426.

The product of its digits is 342921600, while the sum is 69.

The spelling of 21389766763155 in words is "twenty-one trillion, three hundred eighty-nine billion, seven hundred sixty-six million, seven hundred sixty-three thousand, one hundred fifty-five".