11821001 has 16 divisors (see below), whose sum is σ = 13014144. Its totient is φ = 10692864.

The previous prime is 11820971. The next prime is 11821027. The reversal of 11821001 is 10012811.

11821001 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-11821001 is a prime.

It is a Duffinian number.

11821001 is a Rhonda number in base 9.

It is not an unprimeable number, because it can be changed into a prime (11821031) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 75215 + ... + 75371.

It is an arithmetic number, because the mean of its divisors is an integer number (813384).

Almost surely, 2^11821001 is an apocalyptic number.

It is an amenable number.

11821001 is a deficient number, since it is larger than the sum of its proper divisors (1193143).

11821001 is a wasteful number, since it uses less digits than its factorization.

11821001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 320.

The product of its (nonzero) digits is 16, while the sum is 14.

The square root of 11821001 is about 3438.1682623164. The cubic root of 11821001 is about 227.7987926851.

Adding to 11821001 its reverse (10012811), we get a palindrome (21833812).

The spelling of 11821001 in words is "eleven million, eight hundred twenty-one thousand, one".