681754 has 4 divisors (see below), whose sum is σ = 1022634. Its totient is φ = 340876.

The previous prime is 681731. The next prime is 681763. The reversal of 681754 is 457186.

681754 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 457186 = 2 ⋅228593.

It can be written as a sum of positive squares in only one way, i.e., 632025 + 49729 = 795^2 + 223^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 170437 + ... + 170440.

2⁶⁸¹⁷⁵⁴ is an apocalyptic number.

681754 is a deficient number, since it is larger than the sum of its proper divisors (340880).

681754 is a wasteful number, since it uses less digits than its factorization.

681754 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340879.

The product of its digits is 6720, while the sum is 31.

The square root of 681754 is about 825.6839589092. The cubic root of 681754 is about 88.0121367558.

The spelling of 681754 in words is "six hundred eighty-one thousand, seven hundred fifty-four".