90281821 has 8 divisors (see below), whose sum is σ = 103342464. Its totient is φ = 77262000.

The previous prime is 90281819. The next prime is 90281833. The reversal of 90281821 is 12818209.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 90281821 - 2¹ = 90281819 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90281861) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5305 + ... + 14446.

It is an arithmetic number, because the mean of its divisors is an integer number (12917808).

Almost surely, 2^90281821 is an apocalyptic number.

It is an amenable number.

90281821 is a deficient number, since it is larger than the sum of its proper divisors (13060643).

90281821 is a wasteful number, since it uses less digits than its factorization.

90281821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20411.

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 90281821 is about 9501.6746418723. The cubic root of 90281821 is about 448.6077479919.

The spelling of 90281821 in words is "ninety million, two hundred eighty-one thousand, eight hundred twenty-one".