91468561 has 2 divisors, whose sum is σ = 91468562. Its totient is φ = 91468560.

The previous prime is 91468543. The next prime is 91468571. The reversal of 91468561 is 16586419.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74494161 + 16974400 = 8631^2 + 4120^2 .

It is an emirp because it is prime and its reverse (16586419) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91468561 - 2⁹ = 91468049 is a prime.

It is a super-4 number, since 4×91468561⁴ (a number of 33 digits) contains 4444 as substring.

It is not a weakly prime, because it can be changed into another prime (91468571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45734280 + 45734281.

It is an arithmetic number, because the mean of its divisors is an integer number (45734281).

Almost surely, 2^91468561 is an apocalyptic number.

It is an amenable number.

91468561 is a deficient number, since it is larger than the sum of its proper divisors (1).

91468561 is an equidigital number, since it uses as much as digits as its factorization.

91468561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 40.

The square root of 91468561 is about 9563.9197508135. The cubic root of 91468561 is about 450.5648232685.

It can be divided in two parts, 91468 and 561, that added together give a palindrome (92029).

The spelling of 91468561 in words is "ninety-one million, four hundred sixty-eight thousand, five hundred sixty-one".