621618908 has 6 divisors (see below), whose sum is σ = 1087833096. Its totient is φ = 310809452.

The previous prime is 621618901. The next prime is 621619001. The reversal of 621618908 is 809816126.

It is a super-2 number, since 2×621618908² = 772820133566224928, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621618901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77702360 + ... + 77702367.

It is an arithmetic number, because the mean of its divisors is an integer number (181305516).

Almost surely, 2^621618908 is an apocalyptic number.

It is an amenable number.

621618908 is a deficient number, since it is larger than the sum of its proper divisors (466214188).

621618908 is a wasteful number, since it uses less digits than its factorization.

621618908 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155404731 (or 155404729 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 41.

The square root of 621618908 is about 24932.2864575233. The cubic root of 621618908 is about 853.4434285170.

The spelling of 621618908 in words is "six hundred twenty-one million, six hundred eighteen thousand, nine hundred eight".