621129808 has 20 divisors (see below), whose sum is σ = 1296011668. Its totient is φ = 286675200.

The previous prime is 621129791. The next prime is 621129811. The reversal of 621129808 is 808921126.

It can be written as a sum of positive squares in 2 ways, for example, as 56972304 + 564157504 = 7548^2 + 23752^2 .

It is a super-2 number, since 2×621129808² = 771604476772233728, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1492893 + ... + 1493308.

Almost surely, 2^621129808 is an apocalyptic number.

It is an amenable number.

621129808 is an abundant number, since it is smaller than the sum of its proper divisors (674881860).

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

621129808 is a wasteful number, since it uses less digits than its factorization.

621129808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2986222 (or 2986216 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 37.

The square root of 621129808 is about 24922.4759604659. The cubic root of 621129808 is about 853.2195353349.

The spelling of 621129808 in words is "six hundred twenty-one million, one hundred twenty-nine thousand, eight hundred eight".