11381121816 has 64 divisors (see below), whose sum is σ = 29076710400. Its totient is φ = 3710623488.

The previous prime is 11381121811. The next prime is 11381121827. The reversal of 11381121816 is 61812118311.

It is a super-2 number, since 2×11381121816² (a number of 21 digits) contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11381121811) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3058405 + ... + 3062123.

It is an arithmetic number, because the mean of its divisors is an integer number (454323600).

Almost surely, 2^11381121816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11381121816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14538355200).

11381121816 is an abundant number, since it is smaller than the sum of its proper divisors (17695588584).

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

11381121816 is a wasteful number, since it uses less digits than its factorization.

11381121816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6488 (or 6484 counting only the distinct ones).

The product of its digits is 2304, while the sum is 33.

The spelling of 11381121816 in words is "eleven billion, three hundred eighty-one million, one hundred twenty-one thousand, eight hundred sixteen".