621868720 has 40 divisors (see below), whose sum is σ = 1577287440. Its totient is φ = 226133760.

The previous prime is 621868697. The next prime is 621868739. The reversal of 621868720 is 27868126.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 352455 + ... + 354214.

It is an arithmetic number, because the mean of its divisors is an integer number (39432186).

Almost surely, 2^621868720 is an apocalyptic number.

It is an amenable number.

621868720 is an abundant number, since it is smaller than the sum of its proper divisors (955418720).

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

621868720 is a wasteful number, since it uses less digits than its factorization.

621868720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 706693 (or 706687 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 40.

The square root of 621868720 is about 24937.2957635747. The cubic root of 621868720 is about 853.5577385622.

The spelling of 621868720 in words is "six hundred twenty-one million, eight hundred sixty-eight thousand, seven hundred twenty".