18461861 has 8 divisors (see below), whose sum is σ = 20520864. Its totient is φ = 16466320.

The previous prime is 18461857. The next prime is 18461873. The reversal of 18461861 is 16816481.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18461861 - 2² = 18461857 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18461831) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15251 + ... + 16416.

It is an arithmetic number, because the mean of its divisors is an integer number (2565108).

Almost surely, 2^18461861 is an apocalyptic number.

18461861 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18461861 is a deficient number, since it is larger than the sum of its proper divisors (2059003).

18461861 is a wasteful number, since it uses less digits than its factorization.

18461861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31731.

The product of its digits is 9216, while the sum is 35.

The square root of 18461861 is about 4296.7267774435. The cubic root of 18461861 is about 264.2967517461.

The spelling of 18461861 in words is "eighteen million, four hundred sixty-one thousand, eight hundred sixty-one".