621920808 has 128 divisors (see below), whose sum is σ = 1772928000. Its totient is φ = 201942720.

The previous prime is 621920801. The next prime is 621920821. The reversal of 621920808 is 808029126.

621920808 is a `hidden beast` number, since 621 + 9 + 20 + 8 + 0 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (621920801) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1640763 + ... + 1641141.

It is an arithmetic number, because the mean of its divisors is an integer number (13851000).

Almost surely, 2^621920808 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 621920808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (886464000).

621920808 is an abundant number, since it is smaller than the sum of its proper divisors (1151007192).

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

621920808 is a wasteful number, since it uses less digits than its factorization.

621920808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 572 (or 562 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 621920808 is about 24938.3401211869. The cubic root of 621920808 is about 853.5815693552.

The spelling of 621920808 in words is "six hundred twenty-one million, nine hundred twenty thousand, eight hundred eight".