621660621 has 8 divisors (see below), whose sum is σ = 838867680. Its totient is φ = 409446992.

The previous prime is 621660581. The next prime is 621660623. The reversal of 621660621 is 126066126.

621660621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 621660621 - 2¹¹ = 621658573 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621660623) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1248066 + ... + 1248563.

It is an arithmetic number, because the mean of its divisors is an integer number (104858460).

Almost surely, 2^621660621 is an apocalyptic number.

It is an amenable number.

621660621 is a deficient number, since it is larger than the sum of its proper divisors (217207059).

621660621 is a wasteful number, since it uses less digits than its factorization.

621660621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2496715.

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 621660621 is about 24933.1229692552. The cubic root of 621660621 is about 853.4625178600.

The spelling of 621660621 in words is "six hundred twenty-one million, six hundred sixty thousand, six hundred twenty-one".