621221516 has 24 divisors (see below), whose sum is σ = 1121218560. Its totient is φ = 300987792.

The previous prime is 621221509. The next prime is 621221537. The reversal of 621221516 is 615122126.

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, 7625 + ... + 36063.

It is an arithmetic number, because the mean of its divisors is an integer number (46717440).

Almost surely, 2^621221516 is an apocalyptic number.

It is an amenable number.

621221516 is a deficient number, since it is larger than the sum of its proper divisors (499997044).

621221516 is a wasteful number, since it uses less digits than its factorization.

621221516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28613 (or 28611 counting only the distinct ones).

The product of its digits is 1440, while the sum is 26.

The square root of 621221516 is about 24924.3157579100. The cubic root of 621221516 is about 853.2615250583.

The spelling of 621221516 in words is "six hundred twenty-one million, two hundred twenty-one thousand, five hundred sixteen".