673725772865 has 4 divisors (see below), whose sum is σ = 808470927444. Its totient is φ = 538980618288.

The previous prime is 673725772801. The next prime is 673725772871. The reversal of 673725772865 is 568277527376.

It is a Cunningham number, because it is equal to 820808²+1.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 242540490256 + 431185282609 = 492484^2 + 656647^2 .

It is a cyclic number.

It is not a de Polignac number, because 673725772865 - 2⁶ = 673725772801 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67372577282 + ... + 67372577291.

It is an arithmetic number, because the mean of its divisors is an integer number (202117731861).

Almost surely, 2^673725772865 is an apocalyptic number.

It is an amenable number.

673725772865 is a deficient number, since it is larger than the sum of its proper divisors (134745154579).

673725772865 is a wasteful number, since it uses less digits than its factorization.

673725772865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134745154578.

The product of its digits is 207446400, while the sum is 65.

The spelling of 673725772865 in words is "six hundred seventy-three billion, seven hundred twenty-five million, seven hundred seventy-two thousand, eight hundred sixty-five".