1313265121 has 27 divisors (see below), whose sum is σ = 1588054257. Its totient is φ = 1082821320.

The previous prime is 1313265119. The next prime is 1313265127. The reversal of 1313265121 is 1215623131.

It is a happy number.

The square root of 1313265121 is 36239.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 1313265121 - 2¹ = 1313265119 is a prime.

It is a hoax number, since the sum of its digits (25) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1313265127) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 7863780 + ... + 7863946.

Almost surely, 2^1313265121 is an apocalyptic number.

1313265121 is the 36239-th square number.

1313265121 is the 18120-th centered octagonal number.

It is an amenable number.

1313265121 is a deficient number, since it is larger than the sum of its proper divisors (274789136).

1313265121 is an frugal number, since it uses more digits than its factorization.

1313265121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410 (or 205 counting only the distinct ones).

The product of its digits is 1080, while the sum is 25.

The cubic root of 1313265121 is about 1095.0924967908.

Multiplying 1313265121 by its sum of digits (25), we get a square (32831628025 = 181195²).

Adding to 1313265121 its reverse (1215623131), we get a palindrome (2528888252).

The spelling of 1313265121 in words is "one billion, three hundred thirteen million, two hundred sixty-five thousand, one hundred twenty-one".