1131681 has 8 divisors (see below), whose sum is σ = 1516320. Its totient is φ = 750752.

The previous prime is 1131677. The next prime is 1131701. The reversal of 1131681 is 1861311.

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

It is a cyclic number.

It is not a de Polignac number, because 1131681 - 2² = 1131677 is a prime.

It is a super-2 number, since 2×1131681² = 2561403771522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1131671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 111 + ... + 1508.

It is an arithmetic number, because the mean of its divisors is an integer number (189540).

2^1131681 is an apocalyptic number.

It is an amenable number.

1131681 is a deficient number, since it is larger than the sum of its proper divisors (384639).

1131681 is a wasteful number, since it uses less digits than its factorization.

1131681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1855.

The product of its digits is 144, while the sum is 21.

The square root of 1131681 is about 1063.8049633274. The cubic root of 1131681 is about 104.2096670113.

Adding to 1131681 its reverse (1861311), we get a palindrome (2992992).

The spelling of 1131681 in words is "one million, one hundred thirty-one thousand, six hundred eighty-one".