11815684440 has 128 divisors (see below), whose sum is σ = 40673041920. Its totient is φ = 2689920000.

The previous prime is 11815684421. The next prime is 11815684457. The reversal of 11815684440 is 4448651811.

It is a super-2 number, since 2×11815684440² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 11815684392 and 11815684401.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 182820 + ... + 238860.

It is an arithmetic number, because the mean of its divisors is an integer number (317758140).

Almost surely, 2^11815684440 is an apocalyptic number.

11815684440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11815684440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20336520960).

11815684440 is an abundant number, since it is smaller than the sum of its proper divisors (28857357480).

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

11815684440 is a wasteful number, since it uses less digits than its factorization.

11815684440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56313 (or 56309 counting only the distinct ones).

The product of its (nonzero) digits is 122880, while the sum is 42.

The spelling of 11815684440 in words is "eleven billion, eight hundred fifteen million, six hundred eighty-four thousand, four hundred forty".