91518289 has 2 divisors, whose sum is σ = 91518290. Its totient is φ = 91518288.

The previous prime is 91518241. The next prime is 91518337. The reversal of 91518289 is 98281519.

It is a balanced prime because it is at equal distance from previous prime (91518241) and next prime (91518337).

It can be written as a sum of positive squares in only one way, i.e., 50979600 + 40538689 = 7140^2 + 6367^2 .

It is a cyclic number.

It is not a de Polignac number, because 91518289 - 2¹⁵ = 91485521 is a prime.

It is not a weakly prime, because it can be changed into another prime (91518209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45759144 + 45759145.

It is an arithmetic number, because the mean of its divisors is an integer number (45759145).

Almost surely, 2^91518289 is an apocalyptic number.

It is an amenable number.

91518289 is a deficient number, since it is larger than the sum of its proper divisors (1).

91518289 is an equidigital number, since it uses as much as digits as its factorization.

91518289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 43.

The square root of 91518289 is about 9566.5191684332. The cubic root of 91518289 is about 450.6464601652.

The spelling of 91518289 in words is "ninety-one million, five hundred eighteen thousand, two hundred eighty-nine".