681012 has 18 divisors (see below), whose sum is σ = 1721538. Its totient is φ = 226992.

The previous prime is 681011. The next prime is 681019. The reversal of 681012 is 210186.

It can be written as a sum of positive squares in only one way, i.e., 646416 + 34596 = 804^2 + 186^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 681012.

It is not an unprimeable number, because it can be changed into a prime (681011) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9423 + ... + 9494.

It is an arithmetic number, because the mean of its divisors is an integer number (95641).

2⁶⁸¹⁰¹² is an apocalyptic number.

It is an amenable number.

681012 is an abundant number, since it is smaller than the sum of its proper divisors (1040526).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

681012 is a wasteful number, since it uses less digits than its factorization.

681012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18927 (or 18922 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

The square root of 681012 is about 825.2345121237. The cubic root of 681012 is about 87.9801952677.

Adding to 681012 its reverse (210186), we get a palindrome (891198).

It can be divided in two parts, 6 and 81012, that added together give a palindrome (81018).

The spelling of 681012 in words is "six hundred eighty-one thousand, twelve".