18116651 has 4 divisors (see below), whose sum is σ = 20704752. Its totient is φ = 15528552.

The previous prime is 18116597. The next prime is 18116653. The reversal of 18116651 is 15661181.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15661181 = 131 ⋅119551.

It is a cyclic number.

It is not a de Polignac number, because 18116651 - 2⁶ = 18116587 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18116653) 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, 1294040 + ... + 1294053.

It is an arithmetic number, because the mean of its divisors is an integer number (5176188).

Almost surely, 2^18116651 is an apocalyptic number.

18116651 is a deficient number, since it is larger than the sum of its proper divisors (2588101).

18116651 is an equidigital number, since it uses as much as digits as its factorization.

18116651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2588100.

The product of its digits is 1440, while the sum is 29.

The square root of 18116651 is about 4256.3659382154. The cubic root of 18116651 is about 262.6390543679.

The spelling of 18116651 in words is "eighteen million, one hundred sixteen thousand, six hundred fifty-one".