621043836 has 72 divisors (see below), whose sum is σ = 1701616896. Its totient is φ = 175764960.

The previous prime is 621043817. The next prime is 621043873. The reversal of 621043836 is 638340126.

It is a junction number, because it is equal to n+sod(n) for n = 621043797 and 621043806.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 57981 + ... + 67851.

It is an arithmetic number, because the mean of its divisors is an integer number (23633568).

Almost surely, 2^621043836 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 621043836, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (850808448).

621043836 is an abundant number, since it is smaller than the sum of its proper divisors (1080573060).

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

621043836 is a wasteful number, since it uses less digits than its factorization.

621043836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9999 (or 9990 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 33.

The square root of 621043836 is about 24920.7511122759. The cubic root of 621043836 is about 853.1801681615.

The spelling of 621043836 in words is "six hundred twenty-one million, forty-three thousand, eight hundred thirty-six".