91240889 has 2 divisors, whose sum is σ = 91240890. Its totient is φ = 91240888.

The previous prime is 91240871. The next prime is 91240909. The reversal of 91240889 is 98804219.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60715264 + 30525625 = 7792^2 + 5525^2 .

It is a cyclic number.

It is not a de Polignac number, because 91240889 - 2¹² = 91236793 is a prime.

It is not a weakly prime, because it can be changed into another prime (91240829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45620444 + 45620445.

It is an arithmetic number, because the mean of its divisors is an integer number (45620445).

Almost surely, 2^91240889 is an apocalyptic number.

It is an amenable number.

91240889 is a deficient number, since it is larger than the sum of its proper divisors (1).

91240889 is an equidigital number, since it uses as much as digits as its factorization.

91240889 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 41472, while the sum is 41.

The square root of 91240889 is about 9552.0096838309. The cubic root of 91240889 is about 450.1906829746.

It can be divided in two parts, 91240 and 889, that added together give a palindrome (92129).

The spelling of 91240889 in words is "ninety-one million, two hundred forty thousand, eight hundred eighty-nine".