399719513321 has 2 divisors, whose sum is σ = 399719513322. Its totient is φ = 399719513320.

The previous prime is 399719513309. The next prime is 399719513341. The reversal of 399719513321 is 123315917993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 338562223321 + 61157290000 = 581861^2 + 247300^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-399719513321 is a prime.

It is not a weakly prime, because it can be changed into another prime (399719513341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199859756660 + 199859756661.

It is an arithmetic number, because the mean of its divisors is an integer number (199859756661).

Almost surely, 2^399719513321 is an apocalyptic number.

It is an amenable number.

399719513321 is a deficient number, since it is larger than the sum of its proper divisors (1).

399719513321 is an equidigital number, since it uses as much as digits as its factorization.

399719513321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1377810, while the sum is 53.

The spelling of 399719513321 in words is "three hundred ninety-nine billion, seven hundred nineteen million, five hundred thirteen thousand, three hundred twenty-one".