21712772 has 12 divisors (see below), whose sum is σ = 39223296. Its totient is φ = 10506120.

The previous prime is 21712753. The next prime is 21712781. The reversal of 21712772 is 27721712.

It is a super-3 number, since 3×21712772³ (a number of 23 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87428 + ... + 87675.

It is an arithmetic number, because the mean of its divisors is an integer number (3268608).

Almost surely, 2^21712772 is an apocalyptic number.

It is an amenable number.

21712772 is a deficient number, since it is larger than the sum of its proper divisors (17510524).

21712772 is a wasteful number, since it uses less digits than its factorization.

21712772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175138 (or 175136 counting only the distinct ones).

The product of its digits is 2744, while the sum is 29.

The square root of 21712772 is about 4659.6965566440. The cubic root of 21712772 is about 278.9791568128.

The spelling of 21712772 in words is "twenty-one million, seven hundred twelve thousand, seven hundred seventy-two".