16668376891 has 2 divisors, whose sum is σ = 16668376892. Its totient is φ = 16668376890.

The previous prime is 16668376877. The next prime is 16668376969. The reversal of 16668376891 is 19867386661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16668376891 - 2⁵ = 16668376859 is a prime.

It is not a weakly prime, because it can be changed into another prime (16668376831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8334188445 + 8334188446.

It is an arithmetic number, because the mean of its divisors is an integer number (8334188446).

Almost surely, 2^16668376891 is an apocalyptic number.

16668376891 is a deficient number, since it is larger than the sum of its proper divisors (1).

16668376891 is an equidigital number, since it uses as much as digits as its factorization.

16668376891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15676416, while the sum is 61.

The spelling of 16668376891 in words is "sixteen billion, six hundred sixty-eight million, three hundred seventy-six thousand, eight hundred ninety-one".