1212013321 has 4 divisors (see below), whose sum is σ = 1212106500. Its totient is φ = 1211920144.

The previous prime is 1212013279. The next prime is 1212013399. The reversal of 1212013321 is 1233102121.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1233102121 = 97 ⋅12712393.

It can be written as a sum of positive squares in 2 ways, for example, as 808606096 + 403407225 = 28436^2 + 20085^2 .

It is a cyclic number.

It is not a de Polignac number, because 1212013321 - 2²³ = 1203624713 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1212013295 and 1212013304.

It is not an unprimeable number, because it can be changed into a prime (1212016321) 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, 23146 + ... + 54403.

It is an arithmetic number, because the mean of its divisors is an integer number (303026625).

Almost surely, 2^1212013321 is an apocalyptic number.

It is an amenable number.

1212013321 is a deficient number, since it is larger than the sum of its proper divisors (93179).

1212013321 is an equidigital number, since it uses as much as digits as its factorization.

1212013321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93178.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 1212013321 is about 34813.9816883964. The cubic root of 1212013321 is about 1066.1929283778.

Adding to 1212013321 its reverse (1233102121), we get a palindrome (2445115442).

The spelling of 1212013321 in words is "one billion, two hundred twelve million, thirteen thousand, three hundred twenty-one".