65131813 has 2 divisors, whose sum is σ = 65131814. Its totient is φ = 65131812.

The previous prime is 65131789. The next prime is 65131853. The reversal of 65131813 is 31813156.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38526849 + 26604964 = 6207^2 + 5158^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65131813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65131853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32565906 + 32565907.

It is an arithmetic number, because the mean of its divisors is an integer number (32565907).

Almost surely, 2^65131813 is an apocalyptic number.

It is an amenable number.

65131813 is a deficient number, since it is larger than the sum of its proper divisors (1).

65131813 is an equidigital number, since it uses as much as digits as its factorization.

65131813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2160, while the sum is 28.

The square root of 65131813 is about 8070.4283033802. The cubic root of 65131813 is about 402.3441789755.

Adding to 65131813 its reverse (31813156), we get a palindrome (96944969).

The spelling of 65131813 in words is "sixty-five million, one hundred thirty-one thousand, eight hundred thirteen".