90138204 has 192 divisors, whose sum is σ = 275968000. Its totient is φ = 25194240.

The previous prime is 90138203. The next prime is 90138211. The reversal of 90138204 is 40283109.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90138203) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 826902 + ... + 827010.

Almost surely, 2^90138204 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 90138204, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137984000).

90138204 is an abundant number, since it is smaller than the sum of its proper divisors (185829796).

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

90138204 is a wasteful number, since it uses less digits than its factorization.

90138204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185 (or 177 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 90138204 is about 9494.1141766886. The cubic root of 90138204 is about 448.3697455106.

The spelling of 90138204 in words is "ninety million, one hundred thirty-eight thousand, two hundred four".