18387274 has 4 divisors (see below), whose sum is σ = 27580914. Its totient is φ = 9193636.

The previous prime is 18387263. The next prime is 18387277. The reversal of 18387274 is 47278381.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 18122049 + 265225 = 4257^2 + 515^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (18387277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4596817 + ... + 4596820.

Almost surely, 2^18387274 is an apocalyptic number.

18387274 is a deficient number, since it is larger than the sum of its proper divisors (9193640).

18387274 is an equidigital number, since it uses as much as digits as its factorization.

18387274 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9193639.

The product of its digits is 75264, while the sum is 40.

The square root of 18387274 is about 4288.0384793050. The cubic root of 18387274 is about 263.9403465615.

The spelling of 18387274 in words is "eighteen million, three hundred eighty-seven thousand, two hundred seventy-four".