97991148977 has 2 divisors, whose sum is σ = 97991148978. Its totient is φ = 97991148976.

The previous prime is 97991148953. The next prime is 97991149099. The reversal of 97991148977 is 77984119979.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51724859761 + 46266289216 = 227431^2 + 215096^2 .

It is an emirp because it is prime and its reverse (77984119979) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 97991148977 - 2¹⁶ = 97991083441 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 97991148977.

It is not a weakly prime, because it can be changed into another prime (97991148907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 48995574488 + 48995574489.

It is an arithmetic number, because the mean of its divisors is an integer number (48995574489).

Almost surely, 2^97991148977 is an apocalyptic number.

It is an amenable number.

97991148977 is a deficient number, since it is larger than the sum of its proper divisors (1).

97991148977 is an equidigital number, since it uses as much as digits as its factorization.

97991148977 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72013536, while the sum is 71.

The spelling of 97991148977 in words is "ninety-seven billion, nine hundred ninety-one million, one hundred forty-eight thousand, nine hundred seventy-seven".