51165203213 has 2 divisors, whose sum is σ = 51165203214. Its totient is φ = 51165203212.

The previous prime is 51165203209. The next prime is 51165203281. The reversal of 51165203213 is 31230256115.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 34818813604 + 16346389609 = 186598^2 + 127853^2 .

It is a cyclic number.

It is not a de Polignac number, because 51165203213 - 2² = 51165203209 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51165203293) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25582601606 + 25582601607.

It is an arithmetic number, because the mean of its divisors is an integer number (25582601607).

Almost surely, 2^51165203213 is an apocalyptic number.

It is an amenable number.

51165203213 is a deficient number, since it is larger than the sum of its proper divisors (1).

51165203213 is an equidigital number, since it uses as much as digits as its factorization.

51165203213 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5400, while the sum is 29.

Adding to 51165203213 its reverse (31230256115), we get a palindrome (82395459328).

The spelling of 51165203213 in words is "fifty-one billion, one hundred sixty-five million, two hundred three thousand, two hundred thirteen".