12011001221 has 16 divisors (see below), whose sum is σ = 12744197760. Its totient is φ = 11288185920.

The previous prime is 12011001217. The next prime is 12011001229. The reversal of 12011001221 is 12210011021.

It is a cyclic number.

It is not a de Polignac number, because 12011001221 - 2² = 12011001217 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12011001229) 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, 1713095 + ... + 1720091.

It is an arithmetic number, because the mean of its divisors is an integer number (796512360).

Almost surely, 2^12011001221 is an apocalyptic number.

It is an amenable number.

12011001221 is a deficient number, since it is larger than the sum of its proper divisors (733196539).

12011001221 is a wasteful number, since it uses less digits than its factorization.

12011001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7724.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 12011001221 its reverse (12210011021), we get a palindrome (24221012242).

The spelling of 12011001221 in words is "twelve billion, eleven million, one thousand, two hundred twenty-one".