18499378 has 4 divisors (see below), whose sum is σ = 27749070. Its totient is φ = 9249688.

The previous prime is 18499373. The next prime is 18499379. The reversal of 18499378 is 87399481.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87399481 = 13 ⋅6723037.

It can be written as a sum of positive squares in only one way, i.e., 14953689 + 3545689 = 3867^2 + 1883^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (18499373) 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 as a sum of consecutive naturals, namely, 4624843 + ... + 4624846.

Almost surely, 2^18499378 is an apocalyptic number.

18499378 is a deficient number, since it is larger than the sum of its proper divisors (9249692).

18499378 is an equidigital number, since it uses as much as digits as its factorization.

18499378 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9249691.

The product of its digits is 435456, while the sum is 49.

The square root of 18499378 is about 4301.0903268822. The cubic root of 18499378 is about 264.4756595348.

The spelling of 18499378 in words is "eighteen million, four hundred ninety-nine thousand, three hundred seventy-eight".