16506806399 has 2 divisors, whose sum is σ = 16506806400. Its totient is φ = 16506806398.

The previous prime is 16506806383. The next prime is 16506806423. The reversal of 16506806399 is 99360860561.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16506806399 - 2⁴ = 16506806383 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16506806399.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16506800399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8253403199 + 8253403200.

It is an arithmetic number, because the mean of its divisors is an integer number (8253403200).

Almost surely, 2^16506806399 is an apocalyptic number.

16506806399 is a deficient number, since it is larger than the sum of its proper divisors (1).

16506806399 is an equidigital number, since it uses as much as digits as its factorization.

16506806399 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2099520, while the sum is 53.

The spelling of 16506806399 in words is "sixteen billion, five hundred six million, eight hundred six thousand, three hundred ninety-nine".