97959956821 has 2 divisors, whose sum is σ = 97959956822. Its totient is φ = 97959956820.

The previous prime is 97959956777. The next prime is 97959956827. The reversal of 97959956821 is 12865995979.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57030216100 + 40929740721 = 238810^2 + 202311^2 .

It is a cyclic number.

It is not a de Polignac number, because 97959956821 - 2¹³ = 97959948629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (97959956827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 48979978410 + 48979978411.

It is an arithmetic number, because the mean of its divisors is an integer number (48979978411).

Almost surely, 2^97959956821 is an apocalyptic number.

It is an amenable number.

97959956821 is a deficient number, since it is larger than the sum of its proper divisors (1).

97959956821 is an equidigital number, since it uses as much as digits as its factorization.

97959956821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 110224800, while the sum is 70.

The spelling of 97959956821 in words is "ninety-seven billion, nine hundred fifty-nine million, nine hundred fifty-six thousand, eight hundred twenty-one".