21971832 has 32 divisors (see below), whose sum is σ = 55686480. Its totient is φ = 7223040.

The previous prime is 21971827. The next prime is 21971849. The reversal of 21971832 is 23817912.

It is a super-2 number, since 2×21971832² = 965522802872448, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21971793 and 21971802.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4519 + ... + 8022.

Almost surely, 2^21971832 is an apocalyptic number.

It is an amenable number.

21971832 is an abundant number, since it is smaller than the sum of its proper divisors (33714648).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21971832 is a wasteful number, since it uses less digits than its factorization.

21971832 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12623 (or 12619 counting only the distinct ones).

The product of its digits is 6048, while the sum is 33.

The square root of 21971832 is about 4687.4120791755. The cubic root of 21971832 is about 280.0842943484.

The spelling of 21971832 in words is "twenty-one million, nine hundred seventy-one thousand, eight hundred thirty-two".