685337228281 has 4 divisors (see below), whose sum is σ = 685552678564. Its totient is φ = 685121778000.

The previous prime is 685337228249. The next prime is 685337228297. The reversal of 685337228281 is 182822733586.

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 32610581056 + 652726647225 = 180584^2 + 807915^2 .

It is a cyclic number.

It is not a de Polignac number, because 685337228281 - 2⁵ = 685337228249 is a prime.

It is a super-2 number, since 2×685337228281² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (685337228581) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107720370 + ... + 107726731.

It is an arithmetic number, because the mean of its divisors is an integer number (171388169641).

Almost surely, 2^685337228281 is an apocalyptic number.

It is an amenable number.

685337228281 is a deficient number, since it is larger than the sum of its proper divisors (215450283).

685337228281 is a wasteful number, since it uses less digits than its factorization.

685337228281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215450282.

The product of its digits is 7741440, while the sum is 55.

The spelling of 685337228281 in words is "six hundred eighty-five billion, three hundred thirty-seven million, two hundred twenty-eight thousand, two hundred eighty-one".