685397081 has 8 divisors (see below), whose sum is σ = 704905344. Its totient is φ = 666051120.

The previous prime is 685397059. The next prime is 685397117. The reversal of 685397081 is 180793586.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 685397081 - 2¹⁴ = 685380697 is a prime.

It is a super-2 number, since 2×685397081² = 939538317286641122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (685397021) 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, 31985 + ... + 48926.

It is an arithmetic number, because the mean of its divisors is an integer number (88113168).

Almost surely, 2^685397081 is an apocalyptic number.

It is an amenable number.

685397081 is a deficient number, since it is larger than the sum of its proper divisors (19508263).

685397081 is a wasteful number, since it uses less digits than its factorization.

685397081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81151.

The product of its (nonzero) digits is 362880, while the sum is 47.

The square root of 685397081 is about 26180.0894001529. The cubic root of 685397081 is about 881.6862815277.

The spelling of 685397081 in words is "six hundred eighty-five million, three hundred ninety-seven thousand, eighty-one".