1131631 has 4 divisors (see below), whose sum is σ = 1157992. Its totient is φ = 1105272.

The previous prime is 1131629. The next prime is 1131643. The reversal of 1131631 is 1361311.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1131631 - 2¹ = 1131629 is a prime.

It is a super-2 number, since 2×1131631² = 2561177440322, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1131671) 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, 13116 + ... + 13201.

It is an arithmetic number, because the mean of its divisors is an integer number (289498).

2^1131631 is an apocalyptic number.

1131631 is a deficient number, since it is larger than the sum of its proper divisors (26361).

1131631 is an equidigital number, since it uses as much as digits as its factorization.

1131631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26360.

The product of its digits is 54, while the sum is 16.

The square root of 1131631 is about 1063.7814625194. The cubic root of 1131631 is about 104.2081322561.

Adding to 1131631 its reverse (1361311), we get a palindrome (2492942).

The spelling of 1131631 in words is "one million, one hundred thirty-one thousand, six hundred thirty-one".