18387794 has 4 divisors (see below), whose sum is σ = 27581694. Its totient is φ = 9193896.

The previous prime is 18387773. The next prime is 18387821. The reversal of 18387794 is 49778381.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 49778381 = 5801 ⋅8581.

It can be written as a sum of positive squares in only one way, i.e., 18361225 + 26569 = 4285^2 + 163^2 .

It is a super-2 number, since 2×18387794² = 676221936372872, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4596947 + ... + 4596950.

Almost surely, 2^18387794 is an apocalyptic number.

18387794 is a deficient number, since it is larger than the sum of its proper divisors (9193900).

18387794 is an equidigital number, since it uses as much as digits as its factorization.

18387794 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9193899.

The product of its digits is 338688, while the sum is 47.

The square root of 18387794 is about 4288.0991126605. The cubic root of 18387794 is about 263.9428346535.

The spelling of 18387794 in words is "eighteen million, three hundred eighty-seven thousand, seven hundred ninety-four".