16503491 has 2 divisors, whose sum is σ = 16503492. Its totient is φ = 16503490.

The previous prime is 16503469. The next prime is 16503493. The reversal of 16503491 is 19430561.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16503491 is a prime.

It is a Sophie Germain prime.

Together with 16503493, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (16503493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8251745 + 8251746.

It is an arithmetic number, because the mean of its divisors is an integer number (8251746).

Almost surely, 2^16503491 is an apocalyptic number.

16503491 is a deficient number, since it is larger than the sum of its proper divisors (1).

16503491 is an equidigital number, since it uses as much as digits as its factorization.

16503491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3240, while the sum is 29.

The square root of 16503491 is about 4062.4488919862. The cubic root of 16503491 is about 254.6001216886.

The spelling of 16503491 in words is "sixteen million, five hundred three thousand, four hundred ninety-one".