1187728749 has 24 divisors (see below), whose sum is σ = 1865630520. Its totient is φ = 725096448.

The previous prime is 1187728747. The next prime is 1187728769. The reversal of 1187728749 is 9478277811.

It can be written as a sum of positive squares in 4 ways, for example, as 775232649 + 412496100 = 27843^2 + 20310^2 .

It is not a de Polignac number, because 1187728749 - 2¹ = 1187728747 is a prime.

It is a super-2 number, since 2×1187728749² = 2821399162402210002, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1187728695 and 1187728704.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1187728747) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 99244 + ... + 110565.

It is an arithmetic number, because the mean of its divisors is an integer number (77734605).

Almost surely, 2^1187728749 is an apocalyptic number.

It is an amenable number.

1187728749 is a deficient number, since it is larger than the sum of its proper divisors (677901771).

1187728749 is a wasteful number, since it uses less digits than its factorization.

1187728749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209869 (or 209866 counting only the distinct ones).

The product of its digits is 1580544, while the sum is 54.

The square root of 1187728749 is about 34463.4407597384. The cubic root of 1187728749 is about 1059.0238875163.

The spelling of 1187728749 in words is "one billion, one hundred eighty-seven million, seven hundred twenty-eight thousand, seven hundred forty-nine".