1138511820 has 48 divisors (see below), whose sum is σ = 3212955648. Its totient is φ = 301210560.

The previous prime is 1138511813. The next prime is 1138511837. The reversal of 1138511820 is 281158311.

It is a Harshad number since it is a multiple of its sum of digits (30).

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 15 ways as a sum of consecutive naturals, for example, 67086 + ... + 82325.

It is an arithmetic number, because the mean of its divisors is an integer number (66936576).

Almost surely, 2^1138511820 is an apocalyptic number.

1138511820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1138511820 is an abundant number, since it is smaller than the sum of its proper divisors (2074443828).

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

1138511820 is a wasteful number, since it uses less digits than its factorization.

1138511820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149550 (or 149548 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 30.

The square root of 1138511820 is about 33741.8407915158. The cubic root of 1138511820 is about 1044.1891621536.

The spelling of 1138511820 in words is "one billion, one hundred thirty-eight million, five hundred eleven thousand, eight hundred twenty".