1313396221 has 4 divisors (see below), whose sum is σ = 1313476444. Its totient is φ = 1313316000.

The previous prime is 1313396197. The next prime is 1313396311. The reversal of 1313396221 is 1226933131.

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.

It can be written as a sum of positive squares in 2 ways, for example, as 405579321 + 907816900 = 20139^2 + 30130^2 .

It is a 3-Lehmer number, since φ(1313396221) divides (1313396221-1)³.

It is a cyclic number.

It is not a de Polignac number, because 1313396221 - 2¹⁹ = 1312871933 is a prime.

It is a deceptive number, since it divides R_1313396220.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1313396321) 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, 5730 + ... + 51571.

It is an arithmetic number, because the mean of its divisors is an integer number (328369111).

It is a Poulet number, since it divides 2^1313396220-1.

Almost surely, 2^1313396221 is an apocalyptic number.

1313396221 is the 22921-st heptagonal number.

It is an amenable number.

1313396221 is a deficient number, since it is larger than the sum of its proper divisors (80223).

1313396221 is an equidigital number, since it uses as much as digits as its factorization.

1313396221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80222.

The product of its digits is 5832, while the sum is 31.

The square root of 1313396221 is about 36240.8087796065. The cubic root of 1313396221 is about 1095.1289357010.

The spelling of 1313396221 in words is "one billion, three hundred thirteen million, three hundred ninety-six thousand, two hundred twenty-one".