621378765 has 48 divisors (see below), whose sum is σ = 1243172736. Its totient is φ = 281232000.

The previous prime is 621378763. The next prime is 621378803. The reversal of 621378765 is 567873126.

621378765 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 621378765 - 2¹ = 621378763 is a prime.

It is a super-2 number, since 2×621378765² = 772223139185850450, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 621378765.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621378763) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 22050 + ... + 41580.

It is an arithmetic number, because the mean of its divisors is an integer number (25899432).

Almost surely, 2^621378765 is an apocalyptic number.

It is an amenable number.

621378765 is an abundant number, since it is smaller than the sum of its proper divisors (621793971).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

621378765 is a wasteful number, since it uses less digits than its factorization.

621378765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19650 (or 19647 counting only the distinct ones).

The product of its digits is 423360, while the sum is 45.

The square root of 621378765 is about 24927.4700882380. The cubic root of 621378765 is about 853.3335139804. Note that the first 3 decimals are identical.

The spelling of 621378765 in words is "six hundred twenty-one million, three hundred seventy-eight thousand, seven hundred sixty-five".