621923720 has 64 divisors (see below), whose sum is σ = 1552478400. Its totient is φ = 222311680.

The previous prime is 621923717. The next prime is 621923741. The reversal of 621923720 is 27329126.

It is a happy number.

It is a super-2 number, since 2×621923720² = 773578226997276800, which contains 22 as substring.

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, 13982 + ... + 37938.

It is an arithmetic number, because the mean of its divisors is an integer number (24257475).

Almost surely, 2^621923720 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 621923720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (776239200).

621923720 is an abundant number, since it is smaller than the sum of its proper divisors (930554680).

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

621923720 is a wasteful number, since it uses less digits than its factorization.

621923720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24038 (or 24034 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 32.

The square root of 621923720 is about 24938.3985051166. The cubic root of 621923720 is about 853.5829015857.

The spelling of 621923720 in words is "six hundred twenty-one million, nine hundred twenty-three thousand, seven hundred twenty".