1191142056 has 128 divisors (see below), whose sum is σ = 3389299200. Its totient is φ = 346214400.

The previous prime is 1191142033. The next prime is 1191142061. The reversal of 1191142056 is 6502411911.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 423856 + ... + 426656.

It is an arithmetic number, because the mean of its divisors is an integer number (26478900).

Almost surely, 2^1191142056 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1191142056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1694649600).

1191142056 is an abundant number, since it is smaller than the sum of its proper divisors (2198157144).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1191142056 is a wasteful number, since it uses less digits than its factorization.

1191142056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2899 (or 2895 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 30.

The square root of 1191142056 is about 34512.9259263830. The cubic root of 1191142056 is about 1060.0373951445.

Adding to 1191142056 its reverse (6502411911), we get a palindrome (7693553967).

The spelling of 1191142056 in words is "one billion, one hundred ninety-one million, one hundred forty-two thousand, fifty-six".