640621623319 has 2 divisors, whose sum is σ = 640621623320. Its totient is φ = 640621623318.

The previous prime is 640621623227. The next prime is 640621623329. The reversal of 640621623319 is 913326126046.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 640621623319 - 2¹⁵ = 640621590551 is a prime.

It is a super-2 number, since 2×640621623319² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (640621623329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320310811659 + 320310811660.

It is an arithmetic number, because the mean of its divisors is an integer number (320310811660).

Almost surely, 2^640621623319 is an apocalyptic number.

640621623319 is a deficient number, since it is larger than the sum of its proper divisors (1).

640621623319 is an equidigital number, since it uses as much as digits as its factorization.

640621623319 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 279936, while the sum is 43.

The spelling of 640621623319 in words is "six hundred forty billion, six hundred twenty-one million, six hundred twenty-three thousand, three hundred nineteen".