621688373 has 2 divisors, whose sum is σ = 621688374. Its totient is φ = 621688372.

The previous prime is 621688339. The next prime is 621688387. The reversal of 621688373 is 373886126.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 377641489 + 244046884 = 19433^2 + 15622^2 .

It is a cyclic number.

It is not a de Polignac number, because 621688373 - 2¹⁴ = 621671989 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (621688313) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310844186 + 310844187.

It is an arithmetic number, because the mean of its divisors is an integer number (310844187).

Almost surely, 2^621688373 is an apocalyptic number.

It is an amenable number.

621688373 is a deficient number, since it is larger than the sum of its proper divisors (1).

621688373 is an equidigital number, since it uses as much as digits as its factorization.

621688373 is an evil number, because the sum of its binary digits is even.

The product of its digits is 290304, while the sum is 44.

The square root of 621688373 is about 24933.6794918039. The cubic root of 621688373 is about 853.4752176828.

The spelling of 621688373 in words is "six hundred twenty-one million, six hundred eighty-eight thousand, three hundred seventy-three".