12121001001 has 8 divisors (see below), whose sum is σ = 17957038560. Its totient is φ = 8080667316.

The previous prime is 12121000993. The next prime is 12121001017. The reversal of 12121001001 is 10010012121.

It is a happy number.

It is not a de Polignac number, because 12121001001 - 2³ = 12121000993 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 (12121001801) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 224462955 + ... + 224463008.

It is an arithmetic number, because the mean of its divisors is an integer number (2244629820).

Almost surely, 2^12121001001 is an apocalyptic number.

It is an amenable number.

12121001001 is a deficient number, since it is larger than the sum of its proper divisors (5836037559).

12121001001 is an equidigital number, since it uses as much as digits as its factorization.

12121001001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 448925972 (or 448925966 counting only the distinct ones).

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

Adding to 12121001001 its reverse (10010012121), we get a palindrome (22131013122).

The spelling of 12121001001 in words is "twelve billion, one hundred twenty-one million, one thousand, one".