731691 has 6 divisors (see below), whose sum is σ = 1056900. Its totient is φ = 487788.

The previous prime is 731683. The next prime is 731711. The reversal of 731691 is 196137.

731691 is nontrivially palindromic in base 16.

731691 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 731691 - 2³ = 731683 is a prime.

It is not an unprimeable number, because it can be changed into a prime (731611) 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, 40641 + ... + 40658.

It is an arithmetic number, because the mean of its divisors is an integer number (176150).

2⁷³¹⁶⁹¹ is an apocalyptic number.

731691 is a deficient number, since it is larger than the sum of its proper divisors (325209).

731691 is a wasteful number, since it uses less digits than its factorization.

731691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81305 (or 81302 counting only the distinct ones).

The product of its digits is 1134, while the sum is 27.

The square root of 731691 is about 855.3893850171. The cubic root of 731691 is about 90.1106047583.

It can be divided in two parts, 73 and 1691, that added together give a square (1764 = 42²).

The spelling of 731691 in words is "seven hundred thirty-one thousand, six hundred ninety-one".