97765544443221 has 12 divisors (see below), whose sum is σ = 149523773854572. Its totient is φ = 61343086709376.

The previous prime is 97765544443207. The next prime is 97765544443267. The reversal of 97765544443221 is 12234444556779.

97765544443221 is a `hidden beast` number, since 9 + 7 + 7 + 6 + 554 + 4 + 44 + 32 + 2 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 28570414716900 + 69195129726321 = 5345130^2 + 8318361^2 .

It is not a de Polignac number, because 97765544443221 - 2³⁰ = 97764470701397 is a prime.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (97765544443291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 319495243126 + ... + 319495243431.

It is an arithmetic number, because the mean of its divisors is an integer number (12460314487881).

Almost surely, 2^{97765544443221} is an apocalyptic number.

It is an amenable number.

97765544443221 is a deficient number, since it is larger than the sum of its proper divisors (51758229411351).

97765544443221 is a wasteful number, since it uses less digits than its factorization.

97765544443221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 638990486580 (or 638990486577 counting only the distinct ones).

The product of its digits is 203212800, while the sum is 63.

The spelling of 97765544443221 in words is "ninety-seven trillion, seven hundred sixty-five billion, five hundred forty-four million, four hundred forty-three thousand, two hundred twenty-one".