51351719897 has 2 divisors, whose sum is σ = 51351719898. Its totient is φ = 51351719896.

The previous prime is 51351719891. The next prime is 51351719929. The reversal of 51351719897 is 79891715315.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31452667801 + 19899052096 = 177349^2 + 141064^2 .

It is a cyclic number.

It is not a de Polignac number, because 51351719897 - 2³⁰ = 50277978073 is a prime.

It is not a weakly prime, because it can be changed into another prime (51351719891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25675859948 + 25675859949.

It is an arithmetic number, because the mean of its divisors is an integer number (25675859949).

Almost surely, 2^51351719897 is an apocalyptic number.

It is an amenable number.

51351719897 is a deficient number, since it is larger than the sum of its proper divisors (1).

51351719897 is an equidigital number, since it uses as much as digits as its factorization.

51351719897 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2381400, while the sum is 56.

The spelling of 51351719897 in words is "fifty-one billion, three hundred fifty-one million, seven hundred nineteen thousand, eight hundred ninety-seven".