16691659 has 2 divisors, whose sum is σ = 16691660. Its totient is φ = 16691658.

The previous prime is 16691657. The next prime is 16691687. The reversal of 16691659 is 95619661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16691659 - 2¹ = 16691657 is a prime.

It is a super-2 number, since 2×16691659² = 557222960344562, which contains 22 as substring.

Together with 16691657, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (16691651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8345829 + 8345830.

It is an arithmetic number, because the mean of its divisors is an integer number (8345830).

Almost surely, 2^16691659 is an apocalyptic number.

16691659 is a deficient number, since it is larger than the sum of its proper divisors (1).

16691659 is an equidigital number, since it uses as much as digits as its factorization.

16691659 is an evil number, because the sum of its binary digits is even.

The product of its digits is 87480, while the sum is 43.

The square root of 16691659 is about 4085.5426812114. The cubic root of 16691659 is about 255.5640927695.

The spelling of 16691659 in words is "sixteen million, six hundred ninety-one thousand, six hundred fifty-nine".