1212219989 has 2 divisors, whose sum is σ = 1212219990. Its totient is φ = 1212219988.

The previous prime is 1212219971. The next prime is 1212220033. The reversal of 1212219989 is 9899122121.

It is an a-pointer prime, because the next prime (1212220033) can be obtained adding 1212219989 to its sum of digits (44).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 991935025 + 220284964 = 31495^2 + 14842^2 .

It is a cyclic number.

It is not a de Polignac number, because 1212219989 - 2²⁸ = 943784533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1212219949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606109994 + 606109995.

It is an arithmetic number, because the mean of its divisors is an integer number (606109995).

Almost surely, 2^1212219989 is an apocalyptic number.

It is an amenable number.

1212219989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1212219989 is an equidigital number, since it uses as much as digits as its factorization.

1212219989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 44.

The square root of 1212219989 is about 34816.9497371611. The cubic root of 1212219989 is about 1066.2535260167.

The spelling of 1212219989 in words is "one billion, two hundred twelve million, two hundred nineteen thousand, nine hundred eighty-nine".