11721456 has 80 divisors (see below), whose sum is σ = 34481920. Its totient is φ = 3810240.

The previous prime is 11721443. The next prime is 11721473. The reversal of 11721456 is 65412711.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18261 + ... + 18891.

It is an arithmetic number, because the mean of its divisors is an integer number (431024).

Almost surely, 2^11721456 is an apocalyptic number.

11721456 is a gapful number since it is divisible by the number (16) 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 11721456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17240960).

11721456 is an abundant number, since it is smaller than the sum of its proper divisors (22760464).

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

11721456 is a wasteful number, since it uses less digits than its factorization.

11721456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 691 (or 679 counting only the distinct ones).

The product of its digits is 1680, while the sum is 27.

The square root of 11721456 is about 3423.6611981912. The cubic root of 11721456 is about 227.1575558814.

It can be divided in two parts, 1172 and 1456, that added together give a triangular number (2628 = T₇₂).

The spelling of 11721456 in words is "eleven million, seven hundred twenty-one thousand, four hundred fifty-six".