11391840 has 144 divisors (see below), whose sum is σ = 40452048. Its totient is φ = 3027456.

The previous prime is 11391827. The next prime is 11391841. The reversal of 11391840 is 4819311.

11391840 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11391841) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38734 + ... + 39026.

It is an arithmetic number, because the mean of its divisors is an integer number (280917).

Almost surely, 2^11391840 is an apocalyptic number.

11391840 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 11391840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20226024).

11391840 is an abundant number, since it is smaller than the sum of its proper divisors (29060208).

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

11391840 is an equidigital number, since it uses as much as digits as its factorization.

11391840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323 (or 303 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 11391840 is about 3375.1799952003. The cubic root of 11391840 is about 225.0079997156.

The spelling of 11391840 in words is "eleven million, three hundred ninety-one thousand, eight hundred forty".