11721001 has 4 divisors (see below), whose sum is σ = 11970432. Its totient is φ = 11471572.

The previous prime is 11720981. The next prime is 11721013. The reversal of 11721001 is 10012711.

11721001 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 11721001 - 2⁷ = 11720873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11722001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124645 + ... + 124738.

It is an arithmetic number, because the mean of its divisors is an integer number (2992608).

Almost surely, 2^11721001 is an apocalyptic number.

It is an amenable number.

11721001 is a deficient number, since it is larger than the sum of its proper divisors (249431).

11721001 is an equidigital number, since it uses as much as digits as its factorization.

11721001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249430.

The product of its (nonzero) digits is 14, while the sum is 13.

The square root of 11721001 is about 3423.5947482142. The cubic root of 11721001 is about 227.1546165985.

Adding to 11721001 its reverse (10012711), we get a palindrome (21733712).

The spelling of 11721001 in words is "eleven million, seven hundred twenty-one thousand, one".