1220021213 has 12 divisors (see below), whose sum is σ = 1304146620. Its totient is φ = 1139927040.

The previous prime is 1220021203. The next prime is 1220021249. The reversal of 1220021213 is 3121200221.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 262861369 + 957159844 = 16213^2 + 30938^2 .

It is not a de Polignac number, because 1220021213 - 2⁸ = 1220020957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220021203) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5981 + ... + 49757.

It is an arithmetic number, because the mean of its divisors is an integer number (108678885).

Almost surely, 2^1220021213 is an apocalyptic number.

It is an amenable number.

1220021213 is a deficient number, since it is larger than the sum of its proper divisors (84125407).

1220021213 is an equidigital number, since it uses as much as digits as its factorization.

1220021213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43868 (or 43837 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 1220021213 is about 34928.8020550376. The cubic root of 1220021213 is about 1068.5359232062.

Adding to 1220021213 its reverse (3121200221), we get a palindrome (4341221434).

The spelling of 1220021213 in words is "one billion, two hundred twenty million, twenty-one thousand, two hundred thirteen".