643319753 has 2 divisors, whose sum is σ = 643319754. Its totient is φ = 643319752.

The previous prime is 643319723. The next prime is 643319767. The reversal of 643319753 is 357913346.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 443860624 + 199459129 = 21068^2 + 14123^2 .

It is a cyclic number.

It is not a de Polignac number, because 643319753 - 2⁸ = 643319497 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 643319753.

It is not a weakly prime, because it can be changed into another prime (643319723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321659876 + 321659877.

It is an arithmetic number, because the mean of its divisors is an integer number (321659877).

Almost surely, 2^643319753 is an apocalyptic number.

It is an amenable number.

643319753 is a deficient number, since it is larger than the sum of its proper divisors (1).

643319753 is an equidigital number, since it uses as much as digits as its factorization.

643319753 is an evil number, because the sum of its binary digits is even.

The product of its digits is 204120, while the sum is 41.

The square root of 643319753 is about 25363.7487962643. The cubic root of 643319753 is about 863.2613468730.

The spelling of 643319753 in words is "six hundred forty-three million, three hundred nineteen thousand, seven hundred fifty-three".