91328057 has 2 divisors, whose sum is σ = 91328058. Its totient is φ = 91328056.

The previous prime is 91328023. The next prime is 91328059. The reversal of 91328057 is 75082319.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 88755241 + 2572816 = 9421^2 + 1604^2 .

It is a cyclic number.

It is not a de Polignac number, because 91328057 - 2¹⁴ = 91311673 is a prime.

Together with 91328059, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (91328059) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45664028 + 45664029.

It is an arithmetic number, because the mean of its divisors is an integer number (45664029).

Almost surely, 2^91328057 is an apocalyptic number.

It is an amenable number.

91328057 is a deficient number, since it is larger than the sum of its proper divisors (1).

91328057 is an equidigital number, since it uses as much as digits as its factorization.

91328057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 91328057 is about 9556.5714040131. The cubic root of 91328057 is about 450.3340022389.

The spelling of 91328057 in words is "ninety-one million, three hundred twenty-eight thousand, fifty-seven".