91057513 has 2 divisors, whose sum is σ = 91057514. Its totient is φ = 91057512.

The previous prime is 91057511. The next prime is 91057541. The reversal of 91057513 is 31575019.

91057513 = 6747² + 6748².

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 45535504 + 45522009 = 6748^2 + 6747^2 .

It is a cyclic number.

It is not a de Polignac number, because 91057513 - 2¹ = 91057511 is a prime.

Together with 91057511, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (91057511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45528756 + 45528757.

It is an arithmetic number, because the mean of its divisors is an integer number (45528757).

Almost surely, 2^91057513 is an apocalyptic number.

91057513 is the 6748-th centered square number.

It is an amenable number.

91057513 is a deficient number, since it is larger than the sum of its proper divisors (1).

91057513 is an equidigital number, since it uses as much as digits as its factorization.

91057513 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4725, while the sum is 31.

The square root of 91057513 is about 9542.4060383113. The cubic root of 91057513 is about 449.8888828525. Note that the first 5 decimals are identical.

The spelling of 91057513 in words is "ninety-one million, fifty-seven thousand, five hundred thirteen".