21720246330 has 32 divisors (see below), whose sum is σ = 52134326784. Its totient is φ = 5791428416.

The previous prime is 21720246313. The next prime is 21720246343. The reversal of 21720246330 is 3364202712.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 279292 + ... + 348488.

It is an arithmetic number, because the mean of its divisors is an integer number (1629197712).

Almost surely, 2^21720246330 is an apocalyptic number.

21720246330 is an abundant number, since it is smaller than the sum of its proper divisors (30414080454).

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

21720246330 is a wasteful number, since it uses less digits than its factorization.

21720246330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79670.

The product of its (nonzero) digits is 12096, while the sum is 30.

The spelling of 21720246330 in words is "twenty-one billion, seven hundred twenty million, two hundred forty-six thousand, three hundred thirty".