21126722074 has 12 divisors (see below), whose sum is σ = 32444206506. Its totient is φ = 10317699672.

The previous prime is 21126722051. The next prime is 21126722077. The reversal of 21126722074 is 47022762112.

It can be written as a sum of positive squares in only one way, i.e., 15560816049 + 5565906025 = 124743^2 + 74605^2 .

It is a super-2 number, since 2×21126722074² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21126722077) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2852809 + ... + 2860204.

Almost surely, 2^21126722074 is an apocalyptic number.

21126722074 is a deficient number, since it is larger than the sum of its proper divisors (11317484432).

21126722074 is an equidigital number, since it uses as much as digits as its factorization.

21126722074 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5713101 (or 5713058 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 34.

The spelling of 21126722074 in words is "twenty-one billion, one hundred twenty-six million, seven hundred twenty-two thousand, seventy-four".