16161491 has 4 divisors (see below), whose sum is σ = 16188984. Its totient is φ = 16134000.

The previous prime is 16161463. The next prime is 16161493. The reversal of 16161491 is 19416161.

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 16161491 - 2⁶ = 16161427 is a prime.

It is a super-2 number, since 2×16161491² = 522387582686162, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16161493) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12845 + ... + 14046.

It is an arithmetic number, because the mean of its divisors is an integer number (4047246).

Almost surely, 2^16161491 is an apocalyptic number.

16161491 is a deficient number, since it is larger than the sum of its proper divisors (27493).

16161491 is an equidigital number, since it uses as much as digits as its factorization.

16161491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27492.

The product of its digits is 1296, while the sum is 29.

The square root of 16161491 is about 4020.1356942272. The cubic root of 16161491 is about 252.8291482423.

The spelling of 16161491 in words is "sixteen million, one hundred sixty-one thousand, four hundred ninety-one".