16978769 has 2 divisors, whose sum is σ = 16978770. Its totient is φ = 16978768.

The previous prime is 16978721. The next prime is 16978771. The reversal of 16978769 is 96787961.

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., 16908544 + 70225 = 4112^2 + 265^2 .

It is an emirp because it is prime and its reverse (96787961) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16978769 - 2⁸ = 16978513 is a prime.

It is a super-2 number, since 2×16978769² = 576557193510722, which contains 22 as substring.

Together with 16978771, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16978769.

It is not a weakly prime, because it can be changed into another prime (16977769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8489384 + 8489385.

It is an arithmetic number, because the mean of its divisors is an integer number (8489385).

Almost surely, 2^16978769 is an apocalyptic number.

It is an amenable number.

16978769 is a deficient number, since it is larger than the sum of its proper divisors (1).

16978769 is an equidigital number, since it uses as much as digits as its factorization.

16978769 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1143072, while the sum is 53.

The square root of 16978769 is about 4120.5301843331. The cubic root of 16978769 is about 257.0210735343.

The spelling of 16978769 in words is "sixteen million, nine hundred seventy-eight thousand, seven hundred sixty-nine".