18813031 has 4 divisors (see below), whose sum is σ = 18979632. Its totient is φ = 18646432.

The previous prime is 18813023. The next prime is 18813043. The reversal of 18813031 is 13031881.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18813031 - 2³ = 18813023 is a prime.

It is a super-2 number, since 2×18813031² = 707860270813922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18812987 and 18813005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18813731) 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, 83131 + ... + 83356.

It is an arithmetic number, because the mean of its divisors is an integer number (4744908).

Almost surely, 2^18813031 is an apocalyptic number.

18813031 is a deficient number, since it is larger than the sum of its proper divisors (166601).

18813031 is a wasteful number, since it uses less digits than its factorization.

18813031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166600.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 18813031 is about 4337.3991054548. The cubic root of 18813031 is about 265.9620001496.

The spelling of 18813031 in words is "eighteen million, eight hundred thirteen thousand, thirty-one".