51356350421 has 2 divisors, whose sum is σ = 51356350422. Its totient is φ = 51356350420.

The previous prime is 51356350387. The next prime is 51356350471. The reversal of 51356350421 is 12405365315.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49662122500 + 1694227921 = 222850^2 + 41161^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51356350421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51356350471) 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, 25678175210 + 25678175211.

It is an arithmetic number, because the mean of its divisors is an integer number (25678175211).

Almost surely, 2^51356350421 is an apocalyptic number.

It is an amenable number.

51356350421 is a deficient number, since it is larger than the sum of its proper divisors (1).

51356350421 is an equidigital number, since it uses as much as digits as its factorization.

51356350421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 54000, while the sum is 35.

The spelling of 51356350421 in words is "fifty-one billion, three hundred fifty-six million, three hundred fifty thousand, four hundred twenty-one".