21881752 has 16 divisors (see below), whose sum is σ = 41123160. Its totient is φ = 10915584.

The previous prime is 21881723. The next prime is 21881767. The reversal of 21881752 is 25718812.

It is a super-2 number, since 2×21881752² = 957622141179008, which contains 22 as substring.

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 3 ways as a sum of consecutive naturals, for example, 808 + ... + 6664.

Almost surely, 2^21881752 is an apocalyptic number.

It is an amenable number.

21881752 is a deficient number, since it is larger than the sum of its proper divisors (19241408).

21881752 is a wasteful number, since it uses less digits than its factorization.

21881752 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6330 (or 6326 counting only the distinct ones).

The product of its digits is 8960, while the sum is 34.

The square root of 21881752 is about 4677.7934969385. The cubic root of 21881752 is about 279.7010073707.

The spelling of 21881752 in words is "twenty-one million, eight hundred eighty-one thousand, seven hundred fifty-two".