97913456821 has 2 divisors, whose sum is σ = 97913456822. Its totient is φ = 97913456820.

The previous prime is 97913456807. The next prime is 97913456843. The reversal of 97913456821 is 12865431979.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55124465796 + 42788991025 = 234786^2 + 206855^2 .

It is an emirp because it is prime and its reverse (12865431979) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 97913456821 - 2¹¹ = 97913454773 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (97913456801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 48956728410 + 48956728411.

It is an arithmetic number, because the mean of its divisors is an integer number (48956728411).

Almost surely, 2^97913456821 is an apocalyptic number.

It is an amenable number.

97913456821 is a deficient number, since it is larger than the sum of its proper divisors (1).

97913456821 is an equidigital number, since it uses as much as digits as its factorization.

97913456821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3265920, while the sum is 55.

The spelling of 97913456821 in words is "ninety-seven billion, nine hundred thirteen million, four hundred fifty-six thousand, eight hundred twenty-one".