2131706565 has 24 divisors (see below), whose sum is σ = 3831810528. Its totient is φ = 1136909520.

The previous prime is 2131706561. The next prime is 2131706579. The reversal of 2131706565 is 5656071312.

2131706565 is a `hidden beast` number, since 21 + 3 + 1 + 70 + 6 + 565 = 666.

It is not a de Polignac number, because 2131706565 - 2² = 2131706561 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 (2131706561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 876031 + ... + 878460.

It is an arithmetic number, because the mean of its divisors is an integer number (159658772).

Almost surely, 2^2131706565 is an apocalyptic number.

It is an amenable number.

2131706565 is a deficient number, since it is larger than the sum of its proper divisors (1700103963).

2131706565 is an equidigital number, since it uses as much as digits as its factorization.

2131706565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1754511 (or 1754499 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 36.

The square root of 2131706565 is about 46170.4078929351. The cubic root of 2131706565 is about 1286.9918821924.

Adding to 2131706565 its reverse (5656071312), we get a palindrome (7787777877).

The spelling of 2131706565 in words is "two billion, one hundred thirty-one million, seven hundred six thousand, five hundred sixty-five".