51105542209 has 2 divisors, whose sum is σ = 51105542210. Its totient is φ = 51105542208.

The previous prime is 51105542207. The next prime is 51105542219. The reversal of 51105542209 is 90224550115.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40108873984 + 10996668225 = 200272^2 + 104865^2 .

It is a cyclic number.

It is not a de Polignac number, because 51105542209 - 2¹ = 51105542207 is a prime.

It is a super-2 number, since 2×51105542209² (a number of 22 digits) contains 22 as substring.

Together with 51105542207, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (51105542207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25552771104 + 25552771105.

It is an arithmetic number, because the mean of its divisors is an integer number (25552771105).

Almost surely, 2^51105542209 is an apocalyptic number.

It is an amenable number.

51105542209 is a deficient number, since it is larger than the sum of its proper divisors (1).

51105542209 is an equidigital number, since it uses as much as digits as its factorization.

51105542209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18000, while the sum is 34.

The spelling of 51105542209 in words is "fifty-one billion, one hundred five million, five hundred forty-two thousand, two hundred nine".