621921089 has 4 divisors (see below), whose sum is σ = 622006320. Its totient is φ = 621835860.

The previous prime is 621921073. The next prime is 621921103. The reversal of 621921089 is 980129126.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 621921089 - 2⁴ = 621921073 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (621921389) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 30527 + ... + 46644.

It is an arithmetic number, because the mean of its divisors is an integer number (155501580).

Almost surely, 2^621921089 is an apocalyptic number.

It is an amenable number.

621921089 is a deficient number, since it is larger than the sum of its proper divisors (85231).

621921089 is an equidigital number, since it uses as much as digits as its factorization.

621921089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85230.

The product of its (nonzero) digits is 15552, while the sum is 38.

The square root of 621921089 is about 24938.3457550817. The cubic root of 621921089 is about 853.5816979119.

The spelling of 621921089 in words is "six hundred twenty-one million, nine hundred twenty-one thousand, eighty-nine".