16971979 has 2 divisors, whose sum is σ = 16971980. Its totient is φ = 16971978.

The previous prime is 16971961. The next prime is 16972009. The reversal of 16971979 is 97917961.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16971979 is a prime.

It is not a weakly prime, because it can be changed into another prime (16971919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8485989 + 8485990.

It is an arithmetic number, because the mean of its divisors is an integer number (8485990).

Almost surely, 2^16971979 is an apocalyptic number.

16971979 is a deficient number, since it is larger than the sum of its proper divisors (1).

16971979 is an equidigital number, since it uses as much as digits as its factorization.

16971979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 214326, while the sum is 49.

The square root of 16971979 is about 4119.7061788433. The cubic root of 16971979 is about 256.9868070968.

The spelling of 16971979 in words is "sixteen million, nine hundred seventy-one thousand, nine hundred seventy-nine".