21643832715 has 32 divisors (see below), whose sum is σ = 36145184256. Its totient is φ = 11038621440.

The previous prime is 21643832701. The next prime is 21643832737. The reversal of 21643832715 is 51723834612.

It is not a de Polignac number, because 21643832715 - 2⁸ = 21643832459 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2139820 + ... + 2149910.

It is an arithmetic number, because the mean of its divisors is an integer number (1129537008).

Almost surely, 2^21643832715 is an apocalyptic number.

21643832715 is a deficient number, since it is larger than the sum of its proper divisors (14501351541).

21643832715 is a wasteful number, since it uses less digits than its factorization.

21643832715 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16339.

The product of its digits is 241920, while the sum is 42.

The spelling of 21643832715 in words is "twenty-one billion, six hundred forty-three million, eight hundred thirty-two thousand, seven hundred fifteen".