16338991 has 4 divisors (see below), whose sum is σ = 16489000. Its totient is φ = 16188984.

The previous prime is 16338979. The next prime is 16338997. The reversal of 16338991 is 19983361.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 16338991 - 2⁷ = 16338863 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16338997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 74841 + ... + 75058.

It is an arithmetic number, because the mean of its divisors is an integer number (4122250).

Almost surely, 2^16338991 is an apocalyptic number.

16338991 is a deficient number, since it is larger than the sum of its proper divisors (150009).

16338991 is a wasteful number, since it uses less digits than its factorization.

16338991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150008.

The product of its digits is 34992, while the sum is 40.

The square root of 16338991 is about 4042.1517784467. The cubic root of 16338991 is about 253.7513790602.

The spelling of 16338991 in words is "sixteen million, three hundred thirty-eight thousand, nine hundred ninety-one".