1166609591 has 24 divisors (see below), whose sum is σ = 1390779936. Its totient is φ = 975421440.

The previous prime is 1166609539. The next prime is 1166609603. The reversal of 1166609591 is 1959066611.

It is not a de Polignac number, because 1166609591 - 2⁶ = 1166609527 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1166609501) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 335735 + ... + 339191.

It is an arithmetic number, because the mean of its divisors is an integer number (57949164).

Almost surely, 2^1166609591 is an apocalyptic number.

1166609591 is a deficient number, since it is larger than the sum of its proper divisors (224170345).

1166609591 is an equidigital number, since it uses as much as digits as its factorization.

1166609591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3639 (or 3632 counting only the distinct ones).

The product of its (nonzero) digits is 87480, while the sum is 44.

The square root of 1166609591 is about 34155.6670407708. The cubic root of 1166609591 is about 1052.7094321659.

The spelling of 1166609591 in words is "one billion, one hundred sixty-six million, six hundred nine thousand, five hundred ninety-one".