621006645 has 80 divisors (see below), whose sum is σ = 1189058112. Its totient is φ = 276595200.

The previous prime is 621006619. The next prime is 621006649. The reversal of 621006645 is 546600126.

621006645 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 621006645 - 2⁷ = 621006517 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621006649) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1548445 + ... + 1548845.

Almost surely, 2^621006645 is an apocalyptic number.

It is an amenable number.

621006645 is a deficient number, since it is larger than the sum of its proper divisors (568051467).

621006645 is an equidigital number, since it uses as much as digits as its factorization.

621006645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 480 (or 459 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 621006645 is about 24920.0049157299. The cubic root of 621006645 is about 853.1631370197.

The spelling of 621006645 in words is "six hundred twenty-one million, six thousand, six hundred forty-five".