1243221213 has 16 divisors (see below), whose sum is σ = 1846696320. Its totient is φ = 738677184.

The previous prime is 1243221197. The next prime is 1243221223. The reversal of 1243221213 is 3121223421.

It is not a de Polignac number, because 1243221213 - 2⁴ = 1243221197 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1243221213.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243221223) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 548481 + ... + 550742.

It is an arithmetic number, because the mean of its divisors is an integer number (115418520).

Almost surely, 2^1243221213 is an apocalyptic number.

1243221213 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1243221213 is a deficient number, since it is larger than the sum of its proper divisors (603475107).

1243221213 is a wasteful number, since it uses less digits than its factorization.

1243221213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1099268.

The product of its digits is 576, while the sum is 21.

The square root of 1243221213 is about 35259.3422088388. The cubic root of 1243221213 is about 1075.2665538393.

Adding to 1243221213 its reverse (3121223421), we get a palindrome (4364444634).

The spelling of 1243221213 in words is "one billion, two hundred forty-three million, two hundred twenty-one thousand, two hundred thirteen".