1138815944 has 16 divisors (see below), whose sum is σ = 2440320000. Its totient is φ = 488063952.

The previous prime is 1138815943. The next prime is 1138815961. The reversal of 1138815944 is 4495188311.

It is a super-2 number, since 2×1138815944² = 2593803508617222272, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1138815895 and 1138815904.

It is not an unprimeable number, because it can be changed into a prime (1138815943) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10167944 + ... + 10168055.

It is an arithmetic number, because the mean of its divisors is an integer number (152520000).

Almost surely, 2^1138815944 is an apocalyptic number.

1138815944 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

1138815944 is an abundant number, since it is smaller than the sum of its proper divisors (1301504056).

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

1138815944 is a wasteful number, since it uses less digits than its factorization.

1138815944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20336012 (or 20336008 counting only the distinct ones).

The product of its digits is 138240, while the sum is 44.

The square root of 1138815944 is about 33746.3471208366. The cubic root of 1138815944 is about 1044.2821299229.

The spelling of 1138815944 in words is "one billion, one hundred thirty-eight million, eight hundred fifteen thousand, nine hundred forty-four".