21712472 has 32 divisors (see below), whose sum is σ = 41806800. Its totient is φ = 10568064.

The previous prime is 21712469. The next prime is 21712477. The reversal of 21712472 is 27421712.

It is a super-3 number, since 3×21712472³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21712477) 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, 73958 + ... + 74250.

Almost surely, 2^21712472 is an apocalyptic number.

It is an amenable number.

21712472 is a deficient number, since it is larger than the sum of its proper divisors (20094328).

21712472 is a wasteful number, since it uses less digits than its factorization.

21712472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 515 (or 511 counting only the distinct ones).

The product of its digits is 1568, while the sum is 26.

The square root of 21712472 is about 4659.6643655954. The cubic root of 21712472 is about 278.9778719448.

The spelling of 21712472 in words is "twenty-one million, seven hundred twelve thousand, four hundred seventy-two".