21712508 has 6 divisors (see below), whose sum is σ = 37996896. Its totient is φ = 10856252.

The previous prime is 21712477. The next prime is 21712513. The reversal of 21712508 is 80521712.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2714060 + ... + 2714067.

It is an arithmetic number, because the mean of its divisors is an integer number (6332816).

Almost surely, 2^21712508 is an apocalyptic number.

It is an amenable number.

21712508 is a deficient number, since it is larger than the sum of its proper divisors (16284388).

21712508 is a wasteful number, since it uses less digits than its factorization.

21712508 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5428131 (or 5428129 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 26.

The square root of 21712508 is about 4659.6682285330. The cubic root of 21712508 is about 278.9780261296.

The spelling of 21712508 in words is "twenty-one million, seven hundred twelve thousand, five hundred eight".