90221904 has 80 divisors (see below), whose sum is σ = 267363840. Its totient is φ = 29099520.

The previous prime is 90221837. The next prime is 90221909. The reversal of 90221904 is 40912209.

It is a super-2 number, since 2×90221904² = 16279983922770432, which contains 22 as substring.

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 (90221909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10024 + ... + 16760.

It is an arithmetic number, because the mean of its divisors is an integer number (3342048).

Almost surely, 2^90221904 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 90221904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (133681920).

90221904 is an abundant number, since it is smaller than the sum of its proper divisors (177141936).

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

90221904 is a wasteful number, since it uses less digits than its factorization.

90221904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6785 (or 6773 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 90221904 is about 9498.5211480525. The cubic root of 90221904 is about 448.5084840847.

It can be divided in two parts, 90221 and 904, that added together give a cube (91125 = 45³).

The spelling of 90221904 in words is "ninety million, two hundred twenty-one thousand, nine hundred four".