1212012221 has 16 divisors (see below), whose sum is σ = 1408259328. Its totient is φ = 1021680000.

The previous prime is 1212012173. The next prime is 1212012251. The reversal of 1212012221 is 1222102121.

It is a cyclic number.

It is not a de Polignac number, because 1212012221 - 2³⁰ = 138270397 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1212012196 and 1212012205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212012251) 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, 101081 + ... + 112433.

It is an arithmetic number, because the mean of its divisors is an integer number (88016208).

Almost surely, 2^1212012221 is an apocalyptic number.

It is an amenable number.

1212012221 is a deficient number, since it is larger than the sum of its proper divisors (196247107).

1212012221 is a wasteful number, since it uses less digits than its factorization.

1212012221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11612.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 1212012221 is about 34813.9658901424. The cubic root of 1212012221 is about 1066.1926058256.

Adding to 1212012221 its reverse (1222102121), we get a palindrome (2434114342).

The spelling of 1212012221 in words is "one billion, two hundred twelve million, twelve thousand, two hundred twenty-one".