91213523 has 2 divisors, whose sum is σ = 91213524. Its totient is φ = 91213522.

The previous prime is 91213459. The next prime is 91213579. The reversal of 91213523 is 32531219.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 91213523 - 2⁶ = 91213459 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 91213492 and 91213501.

It is not a weakly prime, because it can be changed into another prime (91213123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45606761 + 45606762.

It is an arithmetic number, because the mean of its divisors is an integer number (45606762).

Almost surely, 2^91213523 is an apocalyptic number.

91213523 is a deficient number, since it is larger than the sum of its proper divisors (1).

91213523 is an equidigital number, since it uses as much as digits as its factorization.

91213523 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1620, while the sum is 26.

The square root of 91213523 is about 9550.5771029818. The cubic root of 91213523 is about 450.1456697125.

The spelling of 91213523 in words is "ninety-one million, two hundred thirteen thousand, five hundred twenty-three".