91288007989 has 2 divisors, whose sum is σ = 91288007990. Its totient is φ = 91288007988.

The previous prime is 91288007969. The next prime is 91288008011. The reversal of 91288007989 is 98970088219.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 90927577764 + 360430225 = 301542^2 + 18985^2 .

It is a cyclic number.

It is not a de Polignac number, because 91288007989 - 2¹⁷ = 91287876917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91288007959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45644003994 + 45644003995.

It is an arithmetic number, because the mean of its divisors is an integer number (45644003995).

Almost surely, 2^91288007989 is an apocalyptic number.

It is an amenable number.

91288007989 is a deficient number, since it is larger than the sum of its proper divisors (1).

91288007989 is an equidigital number, since it uses as much as digits as its factorization.

91288007989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5225472, while the sum is 61.

The spelling of 91288007989 in words is "ninety-one billion, two hundred eighty-eight million, seven thousand, nine hundred eighty-nine".