97816921 has 6 divisors (see below), whose sum is σ = 103236522. Its totient is φ = 92668320.

The previous prime is 97816919. The next prime is 97816933. The reversal of 97816921 is 12961879.

It can be written as a sum of positive squares in only one way, i.e., 97239321 + 577600 = 9861^2 + 760^2 .

It is not a de Polignac number, because 97816921 - 2¹ = 97816919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (97816951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 135120 + ... + 135841.

It is an arithmetic number, because the mean of its divisors is an integer number (17206087).

Almost surely, 2^97816921 is an apocalyptic number.

It is an amenable number.

97816921 is a deficient number, since it is larger than the sum of its proper divisors (5419601).

97816921 is a wasteful number, since it uses less digits than its factorization.

97816921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 270999 (or 270980 counting only the distinct ones).

The product of its digits is 54432, while the sum is 43.

The square root of 97816921 is about 9890.2437280383. The cubic root of 97816921 is about 460.7563502154.

The spelling of 97816921 in words is "ninety-seven million, eight hundred sixteen thousand, nine hundred twenty-one".