18170661 has 4 divisors (see below), whose sum is σ = 24227552. Its totient is φ = 12113772.

The previous prime is 18170657. The next prime is 18170693. The reversal of 18170661 is 16607181.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 18170661 - 2² = 18170657 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18170641) 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, 3028441 + ... + 3028446.

It is an arithmetic number, because the mean of its divisors is an integer number (6056888).

Almost surely, 2^18170661 is an apocalyptic number.

It is an amenable number.

18170661 is a deficient number, since it is larger than the sum of its proper divisors (6056891).

18170661 is an equidigital number, since it uses as much as digits as its factorization.

18170661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6056890.

The product of its (nonzero) digits is 2016, while the sum is 30.

The square root of 18170661 is about 4262.7058308075. The cubic root of 18170661 is about 262.8997917087.

The spelling of 18170661 in words is "eighteen million, one hundred seventy thousand, six hundred sixty-one".