18020031 has 4 divisors (see below), whose sum is σ = 24026712. Its totient is φ = 12013352.

The previous prime is 18020027. The next prime is 18020039. The reversal of 18020031 is 13002081.

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: 13002081 = 3 ⋅4334027.

It is a cyclic number.

It is not a de Polignac number, because 18020031 - 2² = 18020027 is a prime.

It is a super-2 number, since 2×18020031² = 649443034481922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18020039) 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, 3003336 + ... + 3003341.

It is an arithmetic number, because the mean of its divisors is an integer number (6006678).

Almost surely, 2^18020031 is an apocalyptic number.

18020031 is a deficient number, since it is larger than the sum of its proper divisors (6006681).

18020031 is an equidigital number, since it uses as much as digits as its factorization.

18020031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6006680.

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 18020031 is about 4245.0007067137. Note that the first 3 decimals coincide. The cubic root of 18020031 is about 262.1713183279.

The spelling of 18020031 in words is "eighteen million, twenty thousand, thirty-one".