18861213 has 8 divisors (see below), whose sum is σ = 28740928. Its totient is φ = 10777824.

The previous prime is 18861209. The next prime is 18861233. The reversal of 18861213 is 31216881.

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

It is not a de Polignac number, because 18861213 - 2² = 18861209 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 (18861233) 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, 449056 + ... + 449097.

It is an arithmetic number, because the mean of its divisors is an integer number (3592616).

Almost surely, 2^18861213 is an apocalyptic number.

It is an amenable number.

18861213 is a deficient number, since it is larger than the sum of its proper divisors (9879715).

18861213 is an equidigital number, since it uses as much as digits as its factorization.

18861213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 898163.

The product of its digits is 2304, while the sum is 30.

The square root of 18861213 is about 4342.9498039927. The cubic root of 18861213 is about 266.1888580978.

The spelling of 18861213 in words is "eighteen million, eight hundred sixty-one thousand, two hundred thirteen".