181000090 has 16 divisors (see below), whose sum is σ = 327801888. Its totient is φ = 71955216.

The previous prime is 181000073. The next prime is 181000097. The reversal of 181000090 is 90000181.

It is a super-2 number, since 2×181000090² = 65522065160016200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (181000097) 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, 53892 + ... + 57151.

It is an arithmetic number, because the mean of its divisors is an integer number (20487618).

Almost surely, 2^181000090 is an apocalyptic number.

181000090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

181000090 is a deficient number, since it is larger than the sum of its proper divisors (146801798).

181000090 is a wasteful number, since it uses less digits than its factorization.

181000090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111213.

The product of its (nonzero) digits is 72, while the sum is 19.

The square root of 181000090 is about 13453.6273918970. The cubic root of 181000090 is about 565.6653763390.

Subtracting from 181000090 its reverse (90000181), we obtain a palindrome (90999909).

The spelling of 181000090 in words is "one hundred eighty-one million, ninety", and thus it is an aban number.