51913318397 has 2 divisors, whose sum is σ = 51913318398. Its totient is φ = 51913318396.

The previous prime is 51913318367. The next prime is 51913318409. The reversal of 51913318397 is 79381331915.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 26944894201 + 24968424196 = 164149^2 + 158014^2 .

It is a cyclic number.

It is not a de Polignac number, because 51913318397 - 2¹² = 51913314301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51913318307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25956659198 + 25956659199.

It is an arithmetic number, because the mean of its divisors is an integer number (25956659199).

Almost surely, 2^51913318397 is an apocalyptic number.

It is an amenable number.

51913318397 is a deficient number, since it is larger than the sum of its proper divisors (1).

51913318397 is an equidigital number, since it uses as much as digits as its factorization.

51913318397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 612360, while the sum is 50.

The spelling of 51913318397 in words is "fifty-one billion, nine hundred thirteen million, three hundred eighteen thousand, three hundred ninety-seven".