81030090 has 32 divisors (see below), whose sum is σ = 194711040. Its totient is φ = 21581504.

The previous prime is 81030023. The next prime is 81030097. The reversal of 81030090 is 9003018.

It is not an unprimeable number, because it can be changed into a prime (81030097) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42232 + ... + 44108.

It is an arithmetic number, because the mean of its divisors is an integer number (6084720).

Almost surely, 2^81030090 is an apocalyptic number.

81030090 is an abundant number, since it is smaller than the sum of its proper divisors (113680950).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81030090 is a wasteful number, since it uses less digits than its factorization.

81030090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3326.

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 81030090 is about 9001.6715114472. The cubic root of 81030090 is about 432.7284413600.

The spelling of 81030090 in words is "eighty-one million, thirty thousand, ninety".