1315681 has 8 divisors (see below), whose sum is σ = 1403784. Its totient is φ = 1228800.

The previous prime is 1315673. The next prime is 1315697. The reversal of 1315681 is 1865131.

It can be written as a sum of positive squares in 4 ways, for example, as 608400 + 707281 = 780^2 + 841^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a 3-Lehmer number, since φ(1315681) divides (1315681-1)³.

It is a cyclic number.

It is not a de Polignac number, because 1315681 - 2³ = 1315673 is a prime.

It is a super-2 number, since 2×1315681² = 3462032987522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1315621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3081 + ... + 3481.

It is an arithmetic number, because the mean of its divisors is an integer number (175473).

2^1315681 is an apocalyptic number.

It is an amenable number.

1315681 is a deficient number, since it is larger than the sum of its proper divisors (88103).

1315681 is a wasteful number, since it uses less digits than its factorization.

1315681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 611.

The product of its digits is 720, while the sum is 25.

The square root of 1315681 is about 1147.0313857955. The cubic root of 1315681 is about 109.5763595184.

The spelling of 1315681 in words is "one million, three hundred fifteen thousand, six hundred eighty-one".