681693 has 4 divisors (see below), whose sum is σ = 908928. Its totient is φ = 454460.

The previous prime is 681689. The next prime is 681719. The reversal of 681693 is 396186.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 681693 - 2² = 681689 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681613) 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, 113613 + ... + 113618.

It is an arithmetic number, because the mean of its divisors is an integer number (227232).

2⁶⁸¹⁶⁹³ is an apocalyptic number.

It is an amenable number.

681693 is a deficient number, since it is larger than the sum of its proper divisors (227235).

681693 is a wasteful number, since it uses less digits than its factorization.

681693 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 227234.

The product of its digits is 7776, while the sum is 33.

The square root of 681693 is about 825.6470190099. The cubic root of 681693 is about 88.0095117129.

The spelling of 681693 in words is "six hundred eighty-one thousand, six hundred ninety-three".