90216730321 has 9 divisors (see below), whose sum is σ = 91603779561. Its totient is φ = 88850388132.

The previous prime is 90216730319. The next prime is 90216730343. The reversal of 90216730321 is 12303761209.

The square root of 90216730321 is 300361.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 90216730321 - 2¹ = 90216730319 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90216730621) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 20121946 + ... + 20126428.

It is an arithmetic number, because the mean of its divisors is an integer number (10178197729).

Almost surely, 2^90216730321 is an apocalyptic number.

90216730321 is the 300361-st square number.

90216730321 is the 150181-st centered octagonal number.

It is an amenable number.

90216730321 is a deficient number, since it is larger than the sum of its proper divisors (1387049240).

90216730321 is an frugal number, since it uses more digits than its factorization.

90216730321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9100 (or 4550 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 34.

The spelling of 90216730321 in words is "ninety billion, two hundred sixteen million, seven hundred thirty thousand, three hundred twenty-one".