21720246352 has 40 divisors (see below), whose sum is σ = 48150775296. Its totient is φ = 9297849216.

The previous prime is 21720246343. The next prime is 21720246389. The reversal of 21720246352 is 25364202712.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15703 + ... + 209014.

Almost surely, 2^21720246352 is an apocalyptic number.

It is an amenable number.

21720246352 is an abundant number, since it is smaller than the sum of its proper divisors (26430528944).

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

21720246352 is a wasteful number, since it uses less digits than its factorization.

21720246352 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225595 (or 225589 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 34.

The spelling of 21720246352 in words is "twenty-one billion, seven hundred twenty million, two hundred forty-six thousand, three hundred fifty-two".