21047321070057 has 4 divisors (see below), whose sum is σ = 28063094760080. Its totient is φ = 14031547380036.

The previous prime is 21047321070043. The next prime is 21047321070067. The reversal of 21047321070057 is 75007012374012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a de Polignac number, because none of the positive numbers 2^k-21047321070057 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21047321069997 and 21047321070024.

It is not an unprimeable number, because it can be changed into a prime (21047321070067) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3507886845007 + ... + 3507886845012.

It is an arithmetic number, because the mean of its divisors is an integer number (7015773690020).

Almost surely, 2^{21047321070057} is an apocalyptic number.

It is an amenable number.

21047321070057 is a deficient number, since it is larger than the sum of its proper divisors (7015773690023).

21047321070057 is an equidigital number, since it uses as much as digits as its factorization.

21047321070057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7015773690022.

The product of its (nonzero) digits is 82320, while the sum is 39.

The spelling of 21047321070057 in words is "twenty-one trillion, forty-seven billion, three hundred twenty-one million, seventy thousand, fifty-seven".