16542491 has 4 divisors (see below), whose sum is σ = 18905712. Its totient is φ = 14179272.

The previous prime is 16542473. The next prime is 16542509. The reversal of 16542491 is 19424561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19424561 = 13 ⋅1494197.

It is an interprime number because it is at equal distance from previous prime (16542473) and next prime (16542509).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16542491 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16542431) 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, 1181600 + ... + 1181613.

It is an arithmetic number, because the mean of its divisors is an integer number (4726428).

Almost surely, 2^16542491 is an apocalyptic number.

16542491 is a deficient number, since it is larger than the sum of its proper divisors (2363221).

16542491 is an equidigital number, since it uses as much as digits as its factorization.

16542491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2363220.

The product of its digits is 8640, while the sum is 32.

The square root of 16542491 is about 4067.2461199195. The cubic root of 16542491 is about 254.8005155222.

The spelling of 16542491 in words is "sixteen million, five hundred forty-two thousand, four hundred ninety-one".