681995 has 4 divisors (see below), whose sum is σ = 818400. Its totient is φ = 545592.

The previous prime is 681983. The next prime is 681997. The reversal of 681995 is 599186.

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

It is a cyclic number.

It is not a de Polignac number, because 681995 - 2⁴ = 681979 is a prime.

It is not an unprimeable number, because it can be changed into a prime (681997) 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, 68195 + ... + 68204.

It is an arithmetic number, because the mean of its divisors is an integer number (204600).

2⁶⁸¹⁹⁹⁵ is an apocalyptic number.

681995 is a deficient number, since it is larger than the sum of its proper divisors (136405).

681995 is a wasteful number, since it uses less digits than its factorization.

681995 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136404.

The product of its digits is 19440, while the sum is 38.

The square root of 681995 is about 825.8298856302. The cubic root of 681995 is about 88.0225062958.

The spelling of 681995 in words is "six hundred eighty-one thousand, nine hundred ninety-five".