91197937 has 2 divisors, whose sum is σ = 91197938. Its totient is φ = 91197936.

The previous prime is 91197913. The next prime is 91197941. The reversal of 91197937 is 73979119.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78694641 + 12503296 = 8871^2 + 3536^2 .

It is an emirp because it is prime and its reverse (73979119) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91197937 is a prime.

It is not a weakly prime, because it can be changed into another prime (91197947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45598968 + 45598969.

It is an arithmetic number, because the mean of its divisors is an integer number (45598969).

Almost surely, 2^91197937 is an apocalyptic number.

It is an amenable number.

91197937 is a deficient number, since it is larger than the sum of its proper divisors (1).

91197937 is an equidigital number, since it uses as much as digits as its factorization.

91197937 is an evil number, because the sum of its binary digits is even.

The product of its digits is 107163, while the sum is 46.

The square root of 91197937 is about 9549.7610964882. The cubic root of 91197937 is about 450.1200288871.

The spelling of 91197937 in words is "ninety-one million, one hundred ninety-seven thousand, nine hundred thirty-seven".