691546873669 has 2 divisors, whose sum is σ = 691546873670. Its totient is φ = 691546873668.

The previous prime is 691546873529. The next prime is 691546873673. The reversal of 691546873669 is 966378645196.

691546873669 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 519394076100 + 172152797569 = 720690^2 + 414913^2 .

It is a cyclic number.

It is not a de Polignac number, because 691546873669 - 2¹⁷ = 691546742597 is a prime.

It is a super-2 number, since 2×691546873669² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 691546873598 and 691546873607.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (691546873769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345773436834 + 345773436835.

It is an arithmetic number, because the mean of its divisors is an integer number (345773436835).

Almost surely, 2^691546873669 is an apocalyptic number.

It is an amenable number.

691546873669 is a deficient number, since it is larger than the sum of its proper divisors (1).

691546873669 is an equidigital number, since it uses as much as digits as its factorization.

691546873669 is an evil number, because the sum of its binary digits is even.

The product of its digits is 352719360, while the sum is 70.

The spelling of 691546873669 in words is "six hundred ninety-one billion, five hundred forty-six million, eight hundred seventy-three thousand, six hundred sixty-nine".