18493231 has 4 divisors (see below), whose sum is σ = 18886752. Its totient is φ = 18099712.

The previous prime is 18493217. The next prime is 18493243. The reversal of 18493231 is 13239481.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13239481 = 17 ⋅778793.

It is a cyclic number.

It is not a de Polignac number, because 18493231 - 2⁵ = 18493199 is a prime.

It is a super-2 number, since 2×18493231² = 683999185638722, 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 = 18493193 and 18493202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18493261) 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, 196690 + ... + 196783.

It is an arithmetic number, because the mean of its divisors is an integer number (4721688).

Almost surely, 2^18493231 is an apocalyptic number.

18493231 is a deficient number, since it is larger than the sum of its proper divisors (393521).

18493231 is an equidigital number, since it uses as much as digits as its factorization.

18493231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 393520.

The product of its digits is 5184, while the sum is 31.

The square root of 18493231 is about 4300.3756812632. The cubic root of 18493231 is about 264.4463628384.

The spelling of 18493231 in words is "eighteen million, four hundred ninety-three thousand, two hundred thirty-one".