16381691 has 2 divisors, whose sum is σ = 16381692. Its totient is φ = 16381690.

The previous prime is 16381661. The next prime is 16381699. The reversal of 16381691 is 19618361.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 16381691 - 2¹⁰ = 16380667 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (16381699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8190845 + 8190846.

It is an arithmetic number, because the mean of its divisors is an integer number (8190846).

Almost surely, 2^16381691 is an apocalyptic number.

16381691 is a deficient number, since it is larger than the sum of its proper divisors (1).

16381691 is an equidigital number, since it uses as much as digits as its factorization.

16381691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7776, while the sum is 35.

The square root of 16381691 is about 4047.4301723439. The cubic root of 16381691 is about 253.9722364099.

The spelling of 16381691 in words is "sixteen million, three hundred eighty-one thousand, six hundred ninety-one".