16965390566401 has 2 divisors, whose sum is σ = 16965390566402. Its totient is φ = 16965390566400.

The previous prime is 16965390566393. The next prime is 16965390566407. The reversal of 16965390566401 is 10466509356961.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11875295063025 + 5090095503376 = 3446055^2 + 2256124^2 .

It is a cyclic number.

It is not a de Polignac number, because 16965390566401 - 2³ = 16965390566393 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16965390566401.

It is not a weakly prime, because it can be changed into another prime (16965390566407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8482695283200 + 8482695283201.

It is an arithmetic number, because the mean of its divisors is an integer number (8482695283201).

Almost surely, 2^{16965390566401} is an apocalyptic number.

It is an amenable number.

16965390566401 is a deficient number, since it is larger than the sum of its proper divisors (1).

16965390566401 is an equidigital number, since it uses as much as digits as its factorization.

16965390566401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31492800, while the sum is 61.

The spelling of 16965390566401 in words is "sixteen trillion, nine hundred sixty-five billion, three hundred ninety million, five hundred sixty-six thousand, four hundred one".