51355316175661 has 2 divisors, whose sum is σ = 51355316175662. Its totient is φ = 51355316175660.

The previous prime is 51355316175659. The next prime is 51355316175679. The reversal of 51355316175661 is 16657161355315.

51355316175661 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., 34997991128100 + 16357325047561 = 5915910^2 + 4044419^2 .

It is a cyclic number.

It is not a de Polignac number, because 51355316175661 - 2¹ = 51355316175659 is a prime.

Together with 51355316175659, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51355316185661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25677658087830 + 25677658087831.

It is an arithmetic number, because the mean of its divisors is an integer number (25677658087831).

Almost surely, 2^{51355316175661} is an apocalyptic number.

It is an amenable number.

51355316175661 is a deficient number, since it is larger than the sum of its proper divisors (1).

51355316175661 is an equidigital number, since it uses as much as digits as its factorization.

51355316175661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8505000, while the sum is 55.

The spelling of 51355316175661 in words is "fifty-one trillion, three hundred fifty-five billion, three hundred sixteen million, one hundred seventy-five thousand, six hundred sixty-one".