685386221 has 8 divisors (see below), whose sum is σ = 776956320. Its totient is φ = 599365872.

The previous prime is 685386181. The next prime is 685386239. The reversal of 685386221 is 122683586.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-685386221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685316221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1387175 + ... + 1387668.

It is an arithmetic number, because the mean of its divisors is an integer number (97119540).

Almost surely, 2^685386221 is an apocalyptic number.

It is an amenable number.

685386221 is a deficient number, since it is larger than the sum of its proper divisors (91570099).

685386221 is a wasteful number, since it uses less digits than its factorization.

685386221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2774875.

The product of its digits is 138240, while the sum is 41.

The square root of 685386221 is about 26179.8819898028. The cubic root of 685386221 is about 881.6816247801.

The spelling of 685386221 in words is "six hundred eighty-five million, three hundred eighty-six thousand, two hundred twenty-one".