90042090 has 32 divisors (see below), whose sum is σ = 221944320. Its totient is φ = 23361984.

The previous prime is 90042089. The next prime is 90042091. The reversal of 90042090 is 9024009.

It is an interprime number because it is at equal distance from previous prime (90042089) and next prime (90042091).

It is a self number, because there is not a number n which added to its sum of digits gives 90042090.

It is not an unprimeable number, because it can be changed into a prime (90042091) 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, 39450 + ... + 41669.

It is an arithmetic number, because the mean of its divisors is an integer number (6935760).

Almost surely, 2^90042090 is an apocalyptic number.

90042090 is an abundant number, since it is smaller than the sum of its proper divisors (131902230).

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

90042090 is a wasteful number, since it uses less digits than its factorization.

90042090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81166.

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 90042090 is about 9489.0510589837. The cubic root of 90042090 is about 448.2103238888.

Adding to 90042090 its reverse (9024009), we get a palindrome (99066099).

The spelling of 90042090 in words is "ninety million, forty-two thousand, ninety".