621809668 has 24 divisors (see below), whose sum is σ = 1097800704. Its totient is φ = 308164800.

The previous prime is 621809633. The next prime is 621809707. The reversal of 621809668 is 866908126.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 236296 + ... + 238912.

It is an arithmetic number, because the mean of its divisors is an integer number (45741696).

Almost surely, 2^621809668 is an apocalyptic number.

It is an amenable number.

621809668 is a deficient number, since it is larger than the sum of its proper divisors (475991036).

621809668 is a wasteful number, since it uses less digits than its factorization.

621809668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3123 (or 3121 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 46.

The square root of 621809668 is about 24936.1117257683. Note that the first 3 decimals coincide. The cubic root of 621809668 is about 853.5307200584.

The spelling of 621809668 in words is "six hundred twenty-one million, eight hundred nine thousand, six hundred sixty-eight".