1212132221 has 4 divisors (see below), whose sum is σ = 1213320444. Its totient is φ = 1210944000.

The previous prime is 1212132217. The next prime is 1212132263. The reversal of 1212132221 is 1222312121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 490135321 + 721996900 = 22139^2 + 26870^2 .

It is a cyclic number.

It is not a de Polignac number, because 1212132221 - 2² = 1212132217 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1212132221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212132121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 592580 + ... + 594621.

It is an arithmetic number, because the mean of its divisors is an integer number (303330111).

Almost surely, 2^1212132221 is an apocalyptic number.

It is an amenable number.

1212132221 is a deficient number, since it is larger than the sum of its proper divisors (1188223).

1212132221 is a wasteful number, since it uses less digits than its factorization.

1212132221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1188222.

The product of its digits is 96, while the sum is 17.

The square root of 1212132221 is about 34815.6892937652. The cubic root of 1212132221 is about 1066.2277921843.

Adding to 1212132221 its reverse (1222312121), we get a palindrome (2434444342).

The spelling of 1212132221 in words is "one billion, two hundred twelve million, one hundred thirty-two thousand, two hundred twenty-one".