91945397 has 2 divisors, whose sum is σ = 91945398. Its totient is φ = 91945396.

The previous prime is 91945391. The next prime is 91945409. The reversal of 91945397 is 79354919.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60124516 + 31820881 = 7754^2 + 5641^2 .

It is a cyclic number.

It is not a de Polignac number, because 91945397 - 2⁸ = 91945141 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91945391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45972698 + 45972699.

It is an arithmetic number, because the mean of its divisors is an integer number (45972699).

Almost surely, 2^91945397 is an apocalyptic number.

It is an amenable number.

91945397 is a deficient number, since it is larger than the sum of its proper divisors (1).

91945397 is an equidigital number, since it uses as much as digits as its factorization.

91945397 is an evil number, because the sum of its binary digits is even.

The product of its digits is 306180, while the sum is 47.

The square root of 91945397 is about 9588.8162460233. The cubic root of 91945397 is about 451.3464151991.

The spelling of 91945397 in words is "ninety-one million, nine hundred forty-five thousand, three hundred ninety-seven".