90085815778 has 64 divisors (see below), whose sum is σ = 166324285440. Its totient is φ = 35717430528.

The previous prime is 90085815739. The next prime is 90085815791. The reversal of 90085815778 is 87751858009.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4257501 + ... + 4278607.

It is an arithmetic number, because the mean of its divisors is an integer number (2598816960).

Almost surely, 2^90085815778 is an apocalyptic number.

90085815778 is a deficient number, since it is larger than the sum of its proper divisors (76238469662).

90085815778 is a wasteful number, since it uses less digits than its factorization.

90085815778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21439.

The product of its (nonzero) digits is 5644800, while the sum is 58.

The spelling of 90085815778 in words is "ninety billion, eighty-five million, eight hundred fifteen thousand, seven hundred seventy-eight".