91616998397 has 2 divisors, whose sum is σ = 91616998398. Its totient is φ = 91616998396.

The previous prime is 91616998393. The next prime is 91616998511. The reversal of 91616998397 is 79389961619.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 57823897156 + 33793101241 = 240466^2 + 183829^2 .

It is a cyclic number.

It is not a de Polignac number, because 91616998397 - 2² = 91616998393 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91616998391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45808499198 + 45808499199.

It is an arithmetic number, because the mean of its divisors is an integer number (45808499199).

Almost surely, 2^91616998397 is an apocalyptic number.

It is an amenable number.

91616998397 is a deficient number, since it is larger than the sum of its proper divisors (1).

91616998397 is an equidigital number, since it uses as much as digits as its factorization.

91616998397 is an evil number, because the sum of its binary digits is even.

The product of its digits is 39680928, while the sum is 68.

The spelling of 91616998397 in words is "ninety-one billion, six hundred sixteen million, nine hundred ninety-eight thousand, three hundred ninety-seven".