90181728 has 384 divisors, whose sum is σ = 343203840. Its totient is φ = 22394880.

The previous prime is 90181727. The next prime is 90181747. The reversal of 90181728 is 82718109.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 90181692 and 90181701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90181727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2437326 + ... + 2437362.

It is an arithmetic number, because the mean of its divisors is an integer number (893760).

Almost surely, 2^90181728 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 90181728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171601920).

90181728 is an abundant number, since it is smaller than the sum of its proper divisors (253022112).

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

90181728 is a wasteful number, since it uses less digits than its factorization.

90181728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107 (or 93 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 36.

The square root of 90181728 is about 9496.4060570302. The cubic root of 90181728 is about 448.4419002826.

It can be divided in two parts, 90181 and 728, that added together give a palindrome (90909).

The spelling of 90181728 in words is "ninety million, one hundred eighty-one thousand, seven hundred twenty-eight".