18491018 has 16 divisors (see below), whose sum is σ = 34137600. Its totient is φ = 7315056.

The previous prime is 18491017. The next prime is 18491021. The reversal of 18491018 is 81019481.

It is not an unprimeable number, because it can be changed into a prime (18491017) 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, 50618 + ... + 50981.

It is an arithmetic number, because the mean of its divisors is an integer number (2133600).

Almost surely, 2^18491018 is an apocalyptic number.

18491018 is a deficient number, since it is larger than the sum of its proper divisors (15646582).

18491018 is a wasteful number, since it uses less digits than its factorization.

18491018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101621.

The product of its (nonzero) digits is 2304, while the sum is 32.

The square root of 18491018 is about 4300.1183704638. The cubic root of 18491018 is about 264.4358140571.

The spelling of 18491018 in words is "eighteen million, four hundred ninety-one thousand, eighteen".