51204640021663 has 2 divisors, whose sum is σ = 51204640021664. Its totient is φ = 51204640021662.

The previous prime is 51204640021517. The next prime is 51204640021669. The reversal of 51204640021663 is 36612004640215.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51204640021663 - 2²¹ = 51204637924511 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51204640021669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25602320010831 + 25602320010832.

It is an arithmetic number, because the mean of its divisors is an integer number (25602320010832).

Almost surely, 2^{51204640021663} is an apocalyptic number.

51204640021663 is a deficient number, since it is larger than the sum of its proper divisors (1).

51204640021663 is an equidigital number, since it uses as much as digits as its factorization.

51204640021663 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 207360, while the sum is 40.

Adding to 51204640021663 its reverse (36612004640215), we get a palindrome (87816644661878).

The spelling of 51204640021663 in words is "fifty-one trillion, two hundred four billion, six hundred forty million, twenty-one thousand, six hundred sixty-three".