51656134109 has 2 divisors, whose sum is σ = 51656134110. Its totient is φ = 51656134108.

The previous prime is 51656134099. The next prime is 51656134129. The reversal of 51656134109 is 90143165615.

51656134109 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40126099225 + 11530034884 = 200315^2 + 107378^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51656134109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51656134129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25828067054 + 25828067055.

It is an arithmetic number, because the mean of its divisors is an integer number (25828067055).

Almost surely, 2^51656134109 is an apocalyptic number.

It is an amenable number.

51656134109 is a deficient number, since it is larger than the sum of its proper divisors (1).

51656134109 is an equidigital number, since it uses as much as digits as its factorization.

51656134109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 97200, while the sum is 41.

The spelling of 51656134109 in words is "fifty-one billion, six hundred fifty-six million, one hundred thirty-four thousand, one hundred nine".