16491599 has 2 divisors, whose sum is σ = 16491600. Its totient is φ = 16491598.

The previous prime is 16491593. The next prime is 16491613. The reversal of 16491599 is 99519461.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16491599 is a prime.

It is a Sophie Germain prime.

It is a plaindrome in base 13.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16491593) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8245799 + 8245800.

It is an arithmetic number, because the mean of its divisors is an integer number (8245800).

Almost surely, 2^16491599 is an apocalyptic number.

16491599 is a deficient number, since it is larger than the sum of its proper divisors (1).

16491599 is an equidigital number, since it uses as much as digits as its factorization.

16491599 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 87480, while the sum is 44.

The square root of 16491599 is about 4060.9849790414. The cubic root of 16491599 is about 254.5389541823.

The spelling of 16491599 in words is "sixteen million, four hundred ninety-one thousand, five hundred ninety-nine".