21702097971 has 24 divisors (see below), whose sum is σ = 33264840960. Its totient is φ = 13604451696.

The previous prime is 21702097931. The next prime is 21702097981. The reversal of 21702097971 is 17979020712.

It is a happy number.

It is not a de Polignac number, because 21702097971 - 2¹¹ = 21702095923 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21702097931) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 876271 + ... + 900696.

It is an arithmetic number, because the mean of its divisors is an integer number (1386035040).

Almost surely, 2^21702097971 is an apocalyptic number.

21702097971 is a deficient number, since it is larger than the sum of its proper divisors (11562742989).

21702097971 is a wasteful number, since it uses less digits than its factorization.

21702097971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1777055 (or 1777052 counting only the distinct ones).

The product of its (nonzero) digits is 111132, while the sum is 45.

The spelling of 21702097971 in words is "twenty-one billion, seven hundred two million, ninety-seven thousand, nine hundred seventy-one".