1138998728 has 32 divisors (see below), whose sum is σ = 2490528000. Its totient is φ = 488141136.

The previous prime is 1138998701. The next prime is 1138998739. The reversal of 1138998728 is 8278998311.

It is a Harshad number since it is a multiple of its sum of digits (56).

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 7 ways as a sum of consecutive naturals, for example, 204800 + ... + 210287.

It is an arithmetic number, because the mean of its divisors is an integer number (77829000).

Almost surely, 2^1138998728 is an apocalyptic number.

It is an amenable number.

1138998728 is an abundant number, since it is smaller than the sum of its proper divisors (1351529272).

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

1138998728 is an equidigital number, since it uses as much as digits as its factorization.

1138998728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 415114 (or 415096 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 56.

The square root of 1138998728 is about 33749.0552164057. The cubic root of 1138998728 is about 1044.3379972631.

The spelling of 1138998728 in words is "one billion, one hundred thirty-eight million, nine hundred ninety-eight thousand, seven hundred twenty-eight".