16491931 has 2 divisors, whose sum is σ = 16491932. Its totient is φ = 16491930.

The previous prime is 16491911. The next prime is 16491949. The reversal of 16491931 is 13919461.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 16491931 - 2¹¹ = 16489883 is a prime.

It is a super-2 number, since 2×16491931² = 543967576217522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (16491911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8245965 + 8245966.

It is an arithmetic number, because the mean of its divisors is an integer number (8245966).

Almost surely, 2^16491931 is an apocalyptic number.

16491931 is a deficient number, since it is larger than the sum of its proper divisors (1).

16491931 is an equidigital number, since it uses as much as digits as its factorization.

16491931 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5832, while the sum is 34.

The square root of 16491931 is about 4061.0258556183. The cubic root of 16491931 is about 254.5406622513.

The spelling of 16491931 in words is "sixteen million, four hundred ninety-one thousand, nine hundred thirty-one".