51305320161 has 8 divisors (see below), whose sum is σ = 76007881760. Its totient is φ = 34203546756.

The previous prime is 51305320151. The next prime is 51305320163. The reversal of 51305320161 is 16102350315.

It is not a de Polignac number, because 51305320161 - 2¹⁰ = 51305319137 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 1900197043 = 51305320161 / (5 + 1 + 3 + 0 + 5 + 3 + 2 + 0 + 1 + 6 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51305320163) 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 7 ways as a sum of consecutive naturals, for example, 950098495 + ... + 950098548.

It is an arithmetic number, because the mean of its divisors is an integer number (9500985220).

Almost surely, 2^51305320161 is an apocalyptic number.

It is an amenable number.

51305320161 is a deficient number, since it is larger than the sum of its proper divisors (24702561599).

51305320161 is a wasteful number, since it uses less digits than its factorization.

51305320161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1900197052 (or 1900197046 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 27.

Adding to 51305320161 its reverse (16102350315), we get a palindrome (67407670476).

The spelling of 51305320161 in words is "fifty-one billion, three hundred five million, three hundred twenty thousand, one hundred sixty-one".