399816360569 has 2 divisors, whose sum is σ = 399816360570. Its totient is φ = 399816360568.

The previous prime is 399816360563. The next prime is 399816360613. The reversal of 399816360569 is 965063618993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 311155342969 + 88661017600 = 557813^2 + 297760^2 .

It is a cyclic number.

It is not a de Polignac number, because 399816360569 - 2²⁰ = 399815311993 is a prime.

It is a super-2 number, since 2×399816360569² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (399816360563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199908180284 + 199908180285.

It is an arithmetic number, because the mean of its divisors is an integer number (199908180285).

Almost surely, 2^399816360569 is an apocalyptic number.

It is an amenable number.

399816360569 is a deficient number, since it is larger than the sum of its proper divisors (1).

399816360569 is an equidigital number, since it uses as much as digits as its factorization.

399816360569 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56687040, while the sum is 65.

The spelling of 399816360569 in words is "three hundred ninety-nine billion, eight hundred sixteen million, three hundred sixty thousand, five hundred sixty-nine".