11591581657 has 2 divisors, whose sum is σ = 11591581658. Its totient is φ = 11591581656.

The previous prime is 11591581633. The next prime is 11591581663. The reversal of 11591581657 is 75618519511.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11473837456 + 117744201 = 107116^2 + 10851^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11591581657 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11591581657.

It is not a weakly prime, because it can be changed into another prime (11591581957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5795790828 + 5795790829.

It is an arithmetic number, because the mean of its divisors is an integer number (5795790829).

Almost surely, 2^11591581657 is an apocalyptic number.

It is an amenable number.

11591581657 is a deficient number, since it is larger than the sum of its proper divisors (1).

11591581657 is an equidigital number, since it uses as much as digits as its factorization.

11591581657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 378000, while the sum is 49.

The spelling of 11591581657 in words is "eleven billion, five hundred ninety-one million, five hundred eighty-one thousand, six hundred fifty-seven".