1213213213 has 4 divisors (see below), whose sum is σ = 1277066560. Its totient is φ = 1149359868.

The previous prime is 1213213193. The next prime is 1213213217. The reversal of 1213213213 is 3123123121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 3123123121 = 37 ⋅84408733.

It is a cyclic number.

It is not a de Polignac number, because 1213213213 - 2⁵ = 1213213181 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 63853327 = 1213213213 / (1 + 2 + 1 + 3 + 2 + 1 + 3 + 2 + 1 + 3).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213213217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31926645 + ... + 31926682.

It is an arithmetic number, because the mean of its divisors is an integer number (319266640).

Almost surely, 2^1213213213 is an apocalyptic number.

It is an amenable number.

1213213213 is a deficient number, since it is larger than the sum of its proper divisors (63853347).

1213213213 is an equidigital number, since it uses as much as digits as its factorization.

1213213213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63853346.

The product of its digits is 216, while the sum is 19.

The square root of 1213213213 is about 34831.2103292435. The cubic root of 1213213213 is about 1066.5446556515.

Adding to 1213213213 its reverse (3123123121), we get a palindrome (4336336334).

It can be divided in two parts, 12 and 13213213, that added together give a square (13213225 = 3635²).

The spelling of 1213213213 in words is "one billion, two hundred thirteen million, two hundred thirteen thousand, two hundred thirteen".