621650643 has 4 divisors (see below), whose sum is σ = 828867528. Its totient is φ = 414433760.

The previous prime is 621650599. The next prime is 621650669. The reversal of 621650643 is 346056126.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 621650643 - 2⁸ = 621650387 is a prime.

It is not an unprimeable number, because it can be changed into a prime (621650243) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 103608438 + ... + 103608443.

It is an arithmetic number, because the mean of its divisors is an integer number (207216882).

Almost surely, 2^621650643 is an apocalyptic number.

621650643 is a deficient number, since it is larger than the sum of its proper divisors (207216885).

621650643 is a wasteful number, since it uses less digits than its factorization.

621650643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207216884.

The product of its (nonzero) digits is 25920, while the sum is 33.

The square root of 621650643 is about 24932.9228731812. The cubic root of 621650643 is about 853.4579516522.

The spelling of 621650643 in words is "six hundred twenty-one million, six hundred fifty thousand, six hundred forty-three".