1220123213 has 4 divisors (see below), whose sum is σ = 1221788508. Its totient is φ = 1218457920.

The previous prime is 1220123207. The next prime is 1220123227. The reversal of 1220123213 is 3123210221.

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 1110355684 + 109767529 = 33322^2 + 10477^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220123213 - 2¹⁶ = 1220057677 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1220123191 and 1220123200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220123273) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 831548 + ... + 833013.

It is an arithmetic number, because the mean of its divisors is an integer number (305447127).

Almost surely, 2^1220123213 is an apocalyptic number.

It is an amenable number.

1220123213 is a deficient number, since it is larger than the sum of its proper divisors (1665295).

1220123213 is an equidigital number, since it uses as much as digits as its factorization.

1220123213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1665294.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 1220123213 is about 34930.2621375792. The cubic root of 1220123213 is about 1068.5657007286.

Adding to 1220123213 its reverse (3123210221), we get a palindrome (4343333434).

The spelling of 1220123213 in words is "one billion, two hundred twenty million, one hundred twenty-three thousand, two hundred thirteen".