681946 has 8 divisors (see below), whose sum is σ = 1026900. Its totient is φ = 339648.

The previous prime is 681943. The next prime is 681949. The reversal of 681946 is 649186.

It is an interprime number because it is at equal distance from previous prime (681943) and next prime (681949).

It can be written as a sum of positive squares in 2 ways, for example, as 585225 + 96721 = 765^2 + 311^2 .

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

It is not an unprimeable number, because it can be changed into a prime (681943) 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, 210 + ... + 1186.

2⁶⁸¹⁹⁴⁶ is an apocalyptic number.

681946 is a deficient number, since it is larger than the sum of its proper divisors (344954).

681946 is a wasteful number, since it uses less digits than its factorization.

681946 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1328.

The product of its digits is 10368, while the sum is 34.

The square root of 681946 is about 825.8002179704. The cubic root of 681946 is about 88.0203981640.

The spelling of 681946 in words is "six hundred eighty-one thousand, nine hundred forty-six".