11666559840 has 384 divisors, whose sum is σ = 41878093824. Its totient is φ = 2709504000.

The previous prime is 11666559811. The next prime is 11666559847. The reversal of 11666559840 is 4895566611.

It is a super-2 number, since 2×11666559840² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11666559847) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7930305 + ... + 7931775.

It is an arithmetic number, because the mean of its divisors is an integer number (109057536).

Almost surely, 2^11666559840 is an apocalyptic number.

11666559840 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 11666559840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20939046912).

11666559840 is an abundant number, since it is smaller than the sum of its proper divisors (30211533984).

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

11666559840 is a wasteful number, since it uses less digits than its factorization.

11666559840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1574 (or 1566 counting only the distinct ones).

The product of its (nonzero) digits is 1555200, while the sum is 51.

The spelling of 11666559840 in words is "eleven billion, six hundred sixty-six million, five hundred fifty-nine thousand, eight hundred forty".