861439420697 has 2 divisors, whose sum is σ = 861439420698. Its totient is φ = 861439420696.

The previous prime is 861439420691. The next prime is 861439420727. The reversal of 861439420697 is 796024934168.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 662109317401 + 199330103296 = 813701^2 + 446464^2 .

It is a cyclic number.

It is not a de Polignac number, because 861439420697 - 2²⁴ = 861422643481 is a prime.

It is not a weakly prime, because it can be changed into another prime (861439420691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430719710348 + 430719710349.

It is an arithmetic number, because the mean of its divisors is an integer number (430719710349).

Almost surely, 2^861439420697 is an apocalyptic number.

It is an amenable number.

861439420697 is a deficient number, since it is larger than the sum of its proper divisors (1).

861439420697 is an equidigital number, since it uses as much as digits as its factorization.

861439420697 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15676416, while the sum is 59.

The spelling of 861439420697 in words is "eight hundred sixty-one billion, four hundred thirty-nine million, four hundred twenty thousand, six hundred ninety-seven".