621999972 has 120 divisors (see below), whose sum is σ = 1784798400. Its totient is φ = 187323840.

The previous prime is 621999949. The next prime is 622000003. The reversal of 621999972 is 279999126.

621999972 is a `hidden beast` number, since 621 + 9 + 9 + 9 + 9 + 7 + 2 = 666.

621999972 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 708798 + ... + 709674.

It is an arithmetic number, because the mean of its divisors is an integer number (14873320).

Almost surely, 2^621999972 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 621999972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (892399200).

621999972 is an abundant number, since it is smaller than the sum of its proper divisors (1162798428).

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

621999972 is a wasteful number, since it uses less digits than its factorization.

621999972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1103 (or 1092 counting only the distinct ones).

The product of its digits is 1102248, while the sum is 54.

The square root of 621999972 is about 24939.9272653310. The cubic root of 621999972 is about 853.6177851475.

The spelling of 621999972 in words is "six hundred twenty-one million, nine hundred ninety-nine thousand, nine hundred seventy-two".