90821821231 has 16 divisors (see below), whose sum is σ = 94228611840. Its totient is φ = 87433758720.

The previous prime is 90821821217. The next prime is 90821821273. The reversal of 90821821231 is 13212812809.

It is a cyclic number.

It is not a de Polignac number, because 90821821231 - 2¹¹ = 90821819183 is a prime.

It is a super-2 number, since 2×90821821231² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90821821031) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16579665 + ... + 16585141.

It is an arithmetic number, because the mean of its divisors is an integer number (5889288240).

Almost surely, 2^90821821231 is an apocalyptic number.

90821821231 is a deficient number, since it is larger than the sum of its proper divisors (3406790609).

90821821231 is a wasteful number, since it uses less digits than its factorization.

90821821231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7074.

The product of its (nonzero) digits is 13824, while the sum is 37.

The spelling of 90821821231 in words is "ninety billion, eight hundred twenty-one million, eight hundred twenty-one thousand, two hundred thirty-one".