51278219701 has 2 divisors, whose sum is σ = 51278219702. Its totient is φ = 51278219700.

The previous prime is 51278219683. The next prime is 51278219743. The reversal of 51278219701 is 10791287215.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29196556900 + 22081662801 = 170870^2 + 148599^2 .

It is a cyclic number.

It is not a de Polignac number, because 51278219701 - 2⁹ = 51278219189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51278219761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25639109850 + 25639109851.

It is an arithmetic number, because the mean of its divisors is an integer number (25639109851).

Almost surely, 2^51278219701 is an apocalyptic number.

It is an amenable number.

51278219701 is a deficient number, since it is larger than the sum of its proper divisors (1).

51278219701 is an equidigital number, since it uses as much as digits as its factorization.

51278219701 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 70560, while the sum is 43.

The spelling of 51278219701 in words is "fifty-one billion, two hundred seventy-eight million, two hundred nineteen thousand, seven hundred one".