1191247872 has 136 divisors (see below), whose sum is σ = 3258949344. Its totient is φ = 386924544.

The previous prime is 1191247867. The next prime is 1191247879. The reversal of 1191247872 is 2787421911.

It is not an unprimeable number, because it can be changed into a prime (1191247879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14352343 + ... + 14352425.

Almost surely, 2^1191247872 is an apocalyptic number.

1191247872 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1191247872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1629474672).

1191247872 is an abundant number, since it is smaller than the sum of its proper divisors (2067701472).

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

1191247872 is an frugal number, since it uses more digits than its factorization.

1191247872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 191 (or 161 counting only the distinct ones).

The product of its digits is 56448, while the sum is 42.

The square root of 1191247872 is about 34514.4588831985. The cubic root of 1191247872 is about 1060.0687839547.

The spelling of 1191247872 in words is "one billion, one hundred ninety-one million, two hundred forty-seven thousand, eight hundred seventy-two".