16516999643 has 2 divisors, whose sum is σ = 16516999644. Its totient is φ = 16516999642.

The previous prime is 16516999633. The next prime is 16516999657. The reversal of 16516999643 is 34699961561.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16516999643 - 2⁴ = 16516999627 is a prime.

It is a super-2 number, since 2×16516999643² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (16516999613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8258499821 + 8258499822.

It is an arithmetic number, because the mean of its divisors is an integer number (8258499822).

Almost surely, 2^16516999643 is an apocalyptic number.

16516999643 is a deficient number, since it is larger than the sum of its proper divisors (1).

16516999643 is an equidigital number, since it uses as much as digits as its factorization.

16516999643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9447840, while the sum is 59.

The spelling of 16516999643 in words is "sixteen billion, five hundred sixteen million, nine hundred ninety-nine thousand, six hundred forty-three".