18881493 has 8 divisors (see below), whose sum is σ = 25342656. Its totient is φ = 12504000.

The previous prime is 18881491. The next prime is 18881501. The reversal of 18881493 is 39418881.

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

It is not a de Polignac number, because 18881493 - 2¹ = 18881491 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18881491) 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, 20388 + ... + 21293.

It is an arithmetic number, because the mean of its divisors is an integer number (3167832).

Almost surely, 2^18881493 is an apocalyptic number.

It is an amenable number.

18881493 is a deficient number, since it is larger than the sum of its proper divisors (6461163).

18881493 is a wasteful number, since it uses less digits than its factorization.

18881493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41835.

The product of its digits is 55296, while the sum is 42.

The square root of 18881493 is about 4345.2839953218. The cubic root of 18881493 is about 266.2842280050.

The spelling of 18881493 in words is "eighteen million, eight hundred eighty-one thousand, four hundred ninety-three".