18861983 has 4 divisors (see below), whose sum is σ = 21556560. Its totient is φ = 16167408.

The previous prime is 18861967. The next prime is 18861989. The reversal of 18861983 is 38916881.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 38916881 = 2699 ⋅14419.

It is a cyclic number.

It is not a de Polignac number, because 18861983 - 2⁴ = 18861967 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 (18861989) 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, 1347278 + ... + 1347291.

It is an arithmetic number, because the mean of its divisors is an integer number (5389140).

Almost surely, 2^18861983 is an apocalyptic number.

18861983 is a deficient number, since it is larger than the sum of its proper divisors (2694577).

18861983 is an equidigital number, since it uses as much as digits as its factorization.

18861983 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2694576.

The product of its digits is 82944, while the sum is 44.

The square root of 18861983 is about 4343.0384525123. The cubic root of 18861983 is about 266.1924803927.

The spelling of 18861983 in words is "eighteen million, eight hundred sixty-one thousand, nine hundred eighty-three".