12201212121 has 40 divisors (see below), whose sum is σ = 19977628320. Its totient is φ = 6605093376.

The previous prime is 12201212113. The next prime is 12201212129. The reversal of 12201212121 is 12121210221.

It is an interprime number because it is at equal distance from previous prime (12201212113) and next prime (12201212129).

It is not a de Polignac number, because 12201212121 - 2³ = 12201212113 is a prime.

12201212121 is a modest number, since divided by 212121 gives 12201 as remainder.

It is a self number, because there is not a number n which added to its sum of digits gives 12201212121.

It is not an unprimeable number, because it can be changed into a prime (12201212129) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 92281 + ... + 181433.

It is an arithmetic number, because the mean of its divisors is an integer number (499440708).

Almost surely, 2^12201212121 is an apocalyptic number.

It is an amenable number.

12201212121 is a deficient number, since it is larger than the sum of its proper divisors (7776416199).

12201212121 is an frugal number, since it uses more digits than its factorization.

12201212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89203 (or 89182 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 12201212121 its reverse (12121210221), we get a palindrome (24322422342).

The spelling of 12201212121 in words is "twelve billion, two hundred one million, two hundred twelve thousand, one hundred twenty-one".