1313681 has 6 divisors (see below), whose sum is σ = 1353282. Its totient is φ = 1274480.

The previous prime is 1313677. The next prime is 1313699. The reversal of 1313681 is 1863131.

It can be written as a sum of positive squares in only one way, i.e., 801025 + 512656 = 895^2 + 716^2 .

It is not a de Polignac number, because 1313681 - 2² = 1313677 is a prime.

It is a super-2 number, since 2×1313681² = 3451515539522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1313621) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7250 + ... + 7428.

It is an arithmetic number, because the mean of its divisors is an integer number (225547).

2^1313681 is an apocalyptic number.

It is an amenable number.

1313681 is a deficient number, since it is larger than the sum of its proper divisors (39601).

1313681 is an frugal number, since it uses more digits than its factorization.

1313681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 399 (or 220 counting only the distinct ones).

The product of its digits is 432, while the sum is 23.

The square root of 1313681 is about 1146.1592385005. The cubic root of 1313681 is about 109.5208080943.

The spelling of 1313681 in words is "one million, three hundred thirteen thousand, six hundred eighty-one".