18451138 has 16 divisors (see below), whose sum is σ = 28788480. Its totient is φ = 8859600.

The previous prime is 18451133. The next prime is 18451151. The reversal of 18451138 is 83115481.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is not an unprimeable number, because it can be changed into a prime (18451133) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7548 + ... + 9688.

It is an arithmetic number, because the mean of its divisors is an integer number (1799280).

Almost surely, 2^18451138 is an apocalyptic number.

18451138 is a deficient number, since it is larger than the sum of its proper divisors (10337342).

18451138 is a wasteful number, since it uses less digits than its factorization.

18451138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2313.

The product of its digits is 3840, while the sum is 31.

The square root of 18451138 is about 4295.4787858864. The cubic root of 18451138 is about 264.2455723094.

The spelling of 18451138 in words is "eighteen million, four hundred fifty-one thousand, one hundred thirty-eight".