1178991 has 12 divisors (see below), whose sum is σ = 1857960. Its totient is φ = 714480.

The previous prime is 1178981. The next prime is 1178993. The reversal of 1178991 is 1998711.

It is not a de Polignac number, because 1178991 - 2⁵ = 1178959 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1178993) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5856 + ... + 6053.

It is an arithmetic number, because the mean of its divisors is an integer number (154830).

2^1178991 is an apocalyptic number.

1178991 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1178991 is a deficient number, since it is larger than the sum of its proper divisors (678969).

1178991 is a wasteful number, since it uses less digits than its factorization.

1178991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11926 (or 11923 counting only the distinct ones).

The product of its digits is 4536, while the sum is 36.

The square root of 1178991 is about 1085.8135199011. The cubic root of 1178991 is about 105.6420523803.

The spelling of 1178991 in words is "one million, one hundred seventy-eight thousand, nine hundred ninety-one".