5161821542309 has 2 divisors, whose sum is σ = 5161821542310. Its totient is φ = 5161821542308.

The previous prime is 5161821542243. The next prime is 5161821542329. The reversal of 5161821542309 is 9032451281615.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3100141961284 + 2061679581025 = 1760722^2 + 1435855^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-5161821542309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5161821542329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2580910771154 + 2580910771155.

It is an arithmetic number, because the mean of its divisors is an integer number (2580910771155).

Almost surely, 2^{5161821542309} is an apocalyptic number.

It is an amenable number.

5161821542309 is a deficient number, since it is larger than the sum of its proper divisors (1).

5161821542309 is an equidigital number, since it uses as much as digits as its factorization.

5161821542309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 518400, while the sum is 47.

The spelling of 5161821542309 in words is "five trillion, one hundred sixty-one billion, eight hundred twenty-one million, five hundred forty-two thousand, three hundred nine".