21875971 has 8 divisors (see below), whose sum is σ = 23683520. Its totient is φ = 20086272.

The previous prime is 21875963. The next prime is 21875977. The reversal of 21875971 is 17957812.

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

It is a cyclic number.

It is not a de Polignac number, because 21875971 - 2³ = 21875963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21875977) 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, 1851 + ... + 6868.

It is an arithmetic number, because the mean of its divisors is an integer number (2960440).

Almost surely, 2^21875971 is an apocalyptic number.

21875971 is a deficient number, since it is larger than the sum of its proper divisors (1807549).

21875971 is a wasteful number, since it uses less digits than its factorization.

21875971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8925.

The product of its digits is 35280, while the sum is 40.

The square root of 21875971 is about 4677.1755365819. The cubic root of 21875971 is about 279.6763735428.

The spelling of 21875971 in words is "twenty-one million, eight hundred seventy-five thousand, nine hundred seventy-one".