21038447738879 has 8 divisors (see below), whose sum is σ = 21395155587840. Its totient is φ = 20681744023000.

The previous prime is 21038447738813. The next prime is 21038447738887. The reversal of 21038447738879 is 97883774483012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21038447738879 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21038447738179) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10273604 + ... + 12150054.

It is an arithmetic number, because the mean of its divisors is an integer number (2674394448480).

Almost surely, 2^{21038447738879} is an apocalyptic number.

21038447738879 is a deficient number, since it is larger than the sum of its proper divisors (356707848961).

21038447738879 is a wasteful number, since it uses less digits than its factorization.

21038447738879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2066541.

The product of its (nonzero) digits is 455196672, while the sum is 71.

The spelling of 21038447738879 in words is "twenty-one trillion, thirty-eight billion, four hundred forty-seven million, seven hundred thirty-eight thousand, eight hundred seventy-nine".