11983840 has 72 divisors (see below), whose sum is σ = 31169880. Its totient is φ = 4350720.

The previous prime is 11983823. The next prime is 11983841. The reversal of 11983840 is 4838911.

It is a happy number.

It is a super-2 number, since 2×11983840² = 287224842291200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 11983796 and 11983805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11983841) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19051 + ... + 19669.

It is an arithmetic number, because the mean of its divisors is an integer number (432915).

Almost surely, 2^11983840 is an apocalyptic number.

11983840 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 11983840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15584940).

11983840 is an abundant number, since it is smaller than the sum of its proper divisors (19186040).

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

11983840 is a wasteful number, since it uses less digits than its factorization.

11983840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 656 (or 637 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 11983840 is about 3461.7683342477. The cubic root of 11983840 is about 228.8400324430.

Subtracting from 11983840 its reverse (4838911), we obtain a square (7144929 = 2673²).

The spelling of 11983840 in words is "eleven million, nine hundred eighty-three thousand, eight hundred forty".