621057647 has 12 divisors (see below), whose sum is σ = 719679600. Its totient is φ = 525011328.

The previous prime is 621057641. The next prime is 621057677. The reversal of 621057647 is 746750126.

It is not a de Polignac number, because 621057647 - 2⁸ = 621057391 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 621057647.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621057641) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 28979 + ... + 45627.

It is an arithmetic number, because the mean of its divisors is an integer number (59973300).

Almost surely, 2^621057647 is an apocalyptic number.

621057647 is a deficient number, since it is larger than the sum of its proper divisors (98621953).

621057647 is an equidigital number, since it uses as much as digits as its factorization.

621057647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16802 (or 16729 counting only the distinct ones).

The product of its (nonzero) digits is 70560, while the sum is 38.

The square root of 621057647 is about 24921.0282091249. The cubic root of 621057647 is about 853.1864925589.

The spelling of 621057647 in words is "six hundred twenty-one million, fifty-seven thousand, six hundred forty-seven".