1166129991 has 24 divisors (see below), whose sum is σ = 1876536480. Its totient is φ = 692870976.

The previous prime is 1166129971. The next prime is 1166130041. The reversal of 1166129991 is 1999216611.

It is not a de Polignac number, because 1166129991 - 2¹⁵ = 1166097223 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1166129911) 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, 168451 + ... + 175236.

It is an arithmetic number, because the mean of its divisors is an integer number (78189020).

Almost surely, 2^1166129991 is an apocalyptic number.

1166129991 is a deficient number, since it is larger than the sum of its proper divisors (710406489).

1166129991 is a wasteful number, since it uses less digits than its factorization.

1166129991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 343735 (or 343732 counting only the distinct ones).

The product of its digits is 52488, while the sum is 45.

The square root of 1166129991 is about 34148.6455221873. The cubic root of 1166129991 is about 1052.5651540658.

The spelling of 1166129991 in words is "one billion, one hundred sixty-six million, one hundred twenty-nine thousand, nine hundred ninety-one".