18181004 has 24 divisors (see below), whose sum is σ = 33094656. Its totient is φ = 8730000.

The previous prime is 18180991. The next prime is 18181013. The reversal of 18181004 is 40018181.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18239 + ... + 19209.

It is an arithmetic number, because the mean of its divisors is an integer number (1378944).

Almost surely, 2^18181004 is an apocalyptic number.

It is an amenable number.

18181004 is a deficient number, since it is larger than the sum of its proper divisors (14913652).

18181004 is a wasteful number, since it uses less digits than its factorization.

18181004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1157 (or 1155 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 23.

The square root of 18181004 is about 4263.9188547626. The cubic root of 18181004 is about 262.9496643538.

Adding to 18181004 its reverse (40018181), we get a palindrome (58199185).

The spelling of 18181004 in words is "eighteen million, one hundred eighty-one thousand, four".