18989078 has 4 divisors (see below), whose sum is σ = 28483620. Its totient is φ = 9494538.

The previous prime is 18989071. The next prime is 18989141. The reversal of 18989078 is 87098981.

It is a happy number.

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

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18989071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4747268 + ... + 4747271.

It is an arithmetic number, because the mean of its divisors is an integer number (7120905).

Almost surely, 2^18989078 is an apocalyptic number.

18989078 is a deficient number, since it is larger than the sum of its proper divisors (9494542).

18989078 is an equidigital number, since it uses as much as digits as its factorization.

18989078 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9494541.

The product of its (nonzero) digits is 290304, while the sum is 50.

The square root of 18989078 is about 4357.6459241200. The cubic root of 18989078 is about 266.7890247511.

The spelling of 18989078 in words is "eighteen million, nine hundred eighty-nine thousand, seventy-eight".