1213211999 has 2 divisors, whose sum is σ = 1213212000. Its totient is φ = 1213211998.

The previous prime is 1213211977. The next prime is 1213212023. The reversal of 1213211999 is 9991123121.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1213211999 - 2⁸ = 1213211743 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1213211929) 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 as a sum of consecutive naturals, namely, 606605999 + 606606000.

It is an arithmetic number, because the mean of its divisors is an integer number (606606000).

Almost surely, 2^1213211999 is an apocalyptic number.

1213211999 is a deficient number, since it is larger than the sum of its proper divisors (1).

1213211999 is an equidigital number, since it uses as much as digits as its factorization.

1213211999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8748, while the sum is 38.

The square root of 1213211999 is about 34831.1929023397. The cubic root of 1213211999 is about 1066.5442999059.

The spelling of 1213211999 in words is "one billion, two hundred thirteen million, two hundred eleven thousand, nine hundred ninety-nine".