621128838 has 16 divisors (see below), whose sum is σ = 1355190336. Its totient is φ = 188220840.

The previous prime is 621128821. The next prime is 621128839. The reversal of 621128838 is 838821126.

It is a junction number, because it is equal to n+sod(n) for n = 621128796 and 621128805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621128839) 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, 4705456 + ... + 4705587.

It is an arithmetic number, because the mean of its divisors is an integer number (84699396).

Almost surely, 2^621128838 is an apocalyptic number.

621128838 is an abundant number, since it is smaller than the sum of its proper divisors (734061498).

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

621128838 is a wasteful number, since it uses less digits than its factorization.

621128838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9411059.

The product of its digits is 36864, while the sum is 39.

The square root of 621128838 is about 24922.4565001125. The cubic root of 621128838 is about 853.2190911854.

The spelling of 621128838 in words is "six hundred twenty-one million, one hundred twenty-eight thousand, eight hundred thirty-eight".