1200121221 has 24 divisors (see below), whose sum is σ = 1737334656. Its totient is φ = 736569600.

The previous prime is 1200121217. The next prime is 1200121229. The reversal of 1200121221 is 1221210021.

It is not a de Polignac number, because 1200121221 - 2² = 1200121217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1200121197 and 1200121206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1200121229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 200356 + ... + 206258.

It is an arithmetic number, because the mean of its divisors is an integer number (72388944).

Almost surely, 2^1200121221 is an apocalyptic number.

It is an amenable number.

1200121221 is a deficient number, since it is larger than the sum of its proper divisors (537213435).

1200121221 is a wasteful number, since it uses less digits than its factorization.

1200121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6333 (or 6320 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 1200121221 is about 34642.7657816174. The cubic root of 1200121221 is about 1062.6943503485.

Adding to 1200121221 its reverse (1221210021), we get a palindrome (2421331242).

The spelling of 1200121221 in words is "one billion, two hundred million, one hundred twenty-one thousand, two hundred twenty-one".