621043817 has 2 divisors, whose sum is σ = 621043818. Its totient is φ = 621043816.

The previous prime is 621043811. The next prime is 621043873. The reversal of 621043817 is 718340126.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 542703616 + 78340201 = 23296^2 + 8851^2 .

It is a cyclic number.

It is not a de Polignac number, because 621043817 - 2²⁰ = 619995241 is a prime.

It is not a weakly prime, because it can be changed into another prime (621043811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310521908 + 310521909.

It is an arithmetic number, because the mean of its divisors is an integer number (310521909).

Almost surely, 2^621043817 is an apocalyptic number.

It is an amenable number.

621043817 is a deficient number, since it is larger than the sum of its proper divisors (1).

621043817 is an equidigital number, since it uses as much as digits as its factorization.

621043817 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 621043817 is about 24920.7507310675. The cubic root of 621043817 is about 853.1801594609.

The spelling of 621043817 in words is "six hundred twenty-one million, forty-three thousand, eight hundred seventeen".