91579777 has 2 divisors, whose sum is σ = 91579778. Its totient is φ = 91579776.

The previous prime is 91579771. The next prime is 91579811. The reversal of 91579777 is 77797519.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 89415936 + 2163841 = 9456^2 + 1471^2 .

It is a cyclic number.

It is not a de Polignac number, because 91579777 - 2¹¹ = 91577729 is a prime.

It is not a weakly prime, because it can be changed into another prime (91579771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45789888 + 45789889.

It is an arithmetic number, because the mean of its divisors is an integer number (45789889).

Almost surely, 2^91579777 is an apocalyptic number.

It is an amenable number.

91579777 is a deficient number, since it is larger than the sum of its proper divisors (1).

91579777 is an equidigital number, since it uses as much as digits as its factorization.

91579777 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 972405, while the sum is 52.

The square root of 91579777 is about 9569.7323369047. The cubic root of 91579777 is about 450.7473622053.

The spelling of 91579777 in words is "ninety-one million, five hundred seventy-nine thousand, seven hundred seventy-seven".