11721000 has 64 divisors (see below), whose sum is σ = 36578880. Its totient is φ = 3124800.

The previous prime is 11720981. The next prime is 11721013. The reversal of 11721000 is 12711.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a zygodrome in base 5.

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 15 ways as a sum of consecutive naturals, for example, 1047 + ... + 4953.

It is an arithmetic number, because the mean of its divisors is an integer number (571545).

Almost surely, 2^11721000 is an apocalyptic number.

11721000 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 11721000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18289440).

11721000 is an abundant number, since it is smaller than the sum of its proper divisors (24857880).

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

11721000 is a wasteful number, since it uses less digits than its factorization.

11721000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3931 (or 3917 counting only the distinct ones).

The product of its (nonzero) digits is 14, while the sum is 12.

The square root of 11721000 is about 3423.5946021689. The cubic root of 11721000 is about 227.1546101385.

Adding to 11721000 its reverse (12711), we get a palindrome (11733711).

The spelling of 11721000 in words is "eleven million, seven hundred twenty-one thousand".