51356021 has 2 divisors, whose sum is σ = 51356022. Its totient is φ = 51356020.

The previous prime is 51356017. The next prime is 51356059. The reversal of 51356021 is 12065315.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43375396 + 7980625 = 6586^2 + 2825^2 .

It is a cyclic number.

It is not a de Polignac number, because 51356021 - 2² = 51356017 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51356621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25678010 + 25678011.

It is an arithmetic number, because the mean of its divisors is an integer number (25678011).

Almost surely, 2^51356021 is an apocalyptic number.

It is an amenable number.

51356021 is a deficient number, since it is larger than the sum of its proper divisors (1).

51356021 is an equidigital number, since it uses as much as digits as its factorization.

51356021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 900, while the sum is 23.

The square root of 51356021 is about 7166.3115338366. The cubic root of 51356021 is about 371.7039040716.

The spelling of 51356021 in words is "fifty-one million, three hundred fifty-six thousand, twenty-one".