681590 has 48 divisors (see below), whose sum is σ = 1551312. Its totient is φ = 213696.

The previous prime is 681589. The next prime is 681607. The reversal of 681590 is 95186.

681590 = 88² + 89² + ... + 139².

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6317 + ... + 6423.

It is an arithmetic number, because the mean of its divisors is an integer number (32319).

2⁶⁸¹⁵⁹⁰ is an apocalyptic number.

681590 is an abundant number, since it is smaller than the sum of its proper divisors (869722).

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

681590 is a wasteful number, since it uses less digits than its factorization.

681590 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141 (or 134 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 681590 is about 825.5846413300. The cubic root of 681590 is about 88.0050789080.

The spelling of 681590 in words is "six hundred eighty-one thousand, five hundred ninety".