1213030321 has 4 divisors (see below), whose sum is σ = 1214822772. Its totient is φ = 1211237872.

The previous prime is 1213030303. The next prime is 1213030337. The reversal of 1213030321 is 1230303121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1230303121 = 10529 ⋅116849.

It can be written as a sum of positive squares in 2 ways, for example, as 1192735296 + 20295025 = 34536^2 + 4505^2 .

It is a cyclic number.

It is not a de Polignac number, because 1213030321 - 2⁵ = 1213030289 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1213030295 and 1213030304.

It is not an unprimeable number, because it can be changed into a prime (1213030391) 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, 895210 + ... + 896563.

It is an arithmetic number, because the mean of its divisors is an integer number (303705693).

Almost surely, 2^1213030321 is an apocalyptic number.

It is an amenable number.

1213030321 is a deficient number, since it is larger than the sum of its proper divisors (1792451).

1213030321 is an equidigital number, since it uses as much as digits as its factorization.

1213030321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1792450.

The product of its (nonzero) digits is 108, while the sum is 16.

The square root of 1213030321 is about 34828.5848262602. The cubic root of 1213030321 is about 1066.4910590575.

Adding to 1213030321 its reverse (1230303121), we get a palindrome (2443333442).

The spelling of 1213030321 in words is "one billion, two hundred thirteen million, thirty thousand, three hundred twenty-one".