90233021 has 4 divisors (see below), whose sum is σ = 90282972. Its totient is φ = 90183072.

The previous prime is 90233009. The next prime is 90233023. The reversal of 90233021 is 12033209.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 64080025 + 26152996 = 8005^2 + 5114^2 .

It is a cyclic number.

It is not a de Polignac number, because 90233021 - 2¹⁰ = 90231997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 90232984 and 90233002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90233023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22160 + ... + 25913.

It is an arithmetic number, because the mean of its divisors is an integer number (22570743).

Almost surely, 2^90233021 is an apocalyptic number.

It is an amenable number.

90233021 is a deficient number, since it is larger than the sum of its proper divisors (49951).

90233021 is a wasteful number, since it uses less digits than its factorization.

90233021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49950.

The product of its (nonzero) digits is 324, while the sum is 20.

The square root of 90233021 is about 9499.1063263867. The cubic root of 90233021 is about 448.5269048296.

The spelling of 90233021 in words is "ninety million, two hundred thirty-three thousand, twenty-one".