18138628 has 12 divisors (see below), whose sum is σ = 33122880. Its totient is φ = 8674952.

The previous prime is 18138623. The next prime is 18138629. The reversal of 18138628 is 82683181.

It is not an unprimeable number, because it can be changed into a prime (18138623) 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, 98488 + ... + 98671.

It is an arithmetic number, because the mean of its divisors is an integer number (2760240).

Almost surely, 2^18138628 is an apocalyptic number.

It is an amenable number.

18138628 is a deficient number, since it is larger than the sum of its proper divisors (14984252).

18138628 is a wasteful number, since it uses less digits than its factorization.

18138628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 197186 (or 197184 counting only the distinct ones).

The product of its digits is 18432, while the sum is 37.

The square root of 18138628 is about 4258.9468181700. The cubic root of 18138628 is about 262.7452124375.

It can be divided in two parts, 181 and 38628, that added together give a square (38809 = 197²).

The spelling of 18138628 in words is "eighteen million, one hundred thirty-eight thousand, six hundred twenty-eight".