1187128979 has 4 divisors (see below), whose sum is σ = 1219213584. Its totient is φ = 1155044376.

The previous prime is 1187128963. The next prime is 1187129051. The reversal of 1187128979 is 9798217811.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1187128979 - 2⁴ = 1187128963 is a prime.

It is a super-3 number, since 3×1187128979³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1187128979.

It is not an unprimeable number, because it can be changed into a prime (1187128909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16042247 + ... + 16042320.

It is an arithmetic number, because the mean of its divisors is an integer number (304803396).

Almost surely, 2^1187128979 is an apocalyptic number.

1187128979 is a deficient number, since it is larger than the sum of its proper divisors (32084605).

1187128979 is an equidigital number, since it uses as much as digits as its factorization.

1187128979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32084604.

The product of its digits is 508032, while the sum is 53.

The square root of 1187128979 is about 34454.7381211931. The cubic root of 1187128979 is about 1058.8455982950.

The spelling of 1187128979 in words is "one billion, one hundred eighty-seven million, one hundred twenty-eight thousand, nine hundred seventy-nine".