16991311 has 2 divisors, whose sum is σ = 16991312. Its totient is φ = 16991310.

The previous prime is 16991309. The next prime is 16991327. The reversal of 16991311 is 11319961.

It is a weak prime.

It is an emirp because it is prime and its reverse (11319961) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16991311 - 2¹ = 16991309 is a prime.

Together with 16991309, it forms a pair of twin primes.

It is equal to p_1090786 and since 16991311 and 1090786 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16991341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8495655 + 8495656.

It is an arithmetic number, because the mean of its divisors is an integer number (8495656).

Almost surely, 2^16991311 is an apocalyptic number.

16991311 is a deficient number, since it is larger than the sum of its proper divisors (1).

16991311 is an equidigital number, since it uses as much as digits as its factorization.

16991311 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1458, while the sum is 31.

The square root of 16991311 is about 4122.0517949196. The cubic root of 16991311 is about 257.0843440202.

The spelling of 16991311 in words is "sixteen million, nine hundred ninety-one thousand, three hundred eleven".