1131131661 has 8 divisors (see below), whose sum is σ = 1645282464. Its totient is φ = 685534320.

The previous prime is 1131131611. The next prime is 1131131663. The reversal of 1131131661 is 1661311311.

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

It is not a de Polignac number, because 1131131661 - 2¹⁷ = 1131000589 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1131131663) 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, 17138326 + ... + 17138391.

It is an arithmetic number, because the mean of its divisors is an integer number (205660308).

Almost surely, 2^1131131661 is an apocalyptic number.

1131131661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1131131661 is a deficient number, since it is larger than the sum of its proper divisors (514150803).

1131131661 is a wasteful number, since it uses less digits than its factorization.

1131131661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34276731.

The product of its digits is 324, while the sum is 24.

The square root of 1131131661 is about 33632.3008579550. The cubic root of 1131131661 is about 1041.9280251222.

Adding to 1131131661 its reverse (1661311311), we get a palindrome (2792442972).

The spelling of 1131131661 in words is "one billion, one hundred thirty-one million, one hundred thirty-one thousand, six hundred sixty-one".