91241389 has 2 divisors, whose sum is σ = 91241390. Its totient is φ = 91241388.

The previous prime is 91241387. The next prime is 91241413. The reversal of 91241389 is 98314219.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 72965764 + 18275625 = 8542^2 + 4275^2 .

It is a cyclic number.

It is not a de Polignac number, because 91241389 - 2¹ = 91241387 is a prime.

Together with 91241387, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91241383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45620694 + 45620695.

It is an arithmetic number, because the mean of its divisors is an integer number (45620695).

Almost surely, 2^91241389 is an apocalyptic number.

It is an amenable number.

91241389 is a deficient number, since it is larger than the sum of its proper divisors (1).

91241389 is an equidigital number, since it uses as much as digits as its factorization.

91241389 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 37.

The square root of 91241389 is about 9552.0358562979. The cubic root of 91241389 is about 450.1915053213.

The spelling of 91241389 in words is "ninety-one million, two hundred forty-one thousand, three hundred eighty-nine".