12011021001 has 24 divisors (see below), whose sum is σ = 19830794880. Its totient is φ = 6862375296.

The previous prime is 12011020951. The next prime is 12011021003. The reversal of 12011021001 is 10012011021.

It is a happy number.

It is not a de Polignac number, because 12011021001 - 2⁷ = 12011020873 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12011021003) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 587121 + ... + 607233.

It is an arithmetic number, because the mean of its divisors is an integer number (826283120).

Almost surely, 2^12011021001 is an apocalyptic number.

It is an amenable number.

12011021001 is a deficient number, since it is larger than the sum of its proper divisors (7819773879).

12011021001 is a wasteful number, since it uses less digits than its factorization.

12011021001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29605 (or 29602 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 12011021001 its reverse (10012011021), we get a palindrome (22023032022).

The spelling of 12011021001 in words is "twelve billion, eleven million, twenty-one thousand, one".