18531493 has 8 divisors (see below), whose sum is σ = 19404000. Its totient is φ = 17674608.

The previous prime is 18531439. The next prime is 18531511. The reversal of 18531493 is 39413581.

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

It is a cyclic number.

It is not a de Polignac number, because 18531493 - 2¹³ = 18523301 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 (18531433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1443 + ... + 6256.

It is an arithmetic number, because the mean of its divisors is an integer number (2425500).

Almost surely, 2^18531493 is an apocalyptic number.

It is an amenable number.

18531493 is a deficient number, since it is larger than the sum of its proper divisors (872507).

18531493 is an equidigital number, since it uses as much as digits as its factorization.

18531493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7811.

The product of its digits is 12960, while the sum is 34.

The square root of 18531493 is about 4304.8220636863. The cubic root of 18531493 is about 264.6286146872.

The spelling of 18531493 in words is "eighteen million, five hundred thirty-one thousand, four hundred ninety-three".