691938 has 24 divisors (see below), whose sum is σ = 1615068. Its totient is φ = 212832.

The previous prime is 691931. The next prime is 691949. The reversal of 691938 is 839196.

691938 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 603729 + 88209 = 777^2 + 297^2 .

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 691938.

It is not an unprimeable number, because it can be changed into a prime (691931) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1245 + ... + 1712.

2⁶⁹¹⁹³⁸ is an apocalyptic number.

691938 is an abundant number, since it is smaller than the sum of its proper divisors (923130).

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

691938 is a wasteful number, since it uses less digits than its factorization.

691938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2978 (or 2975 counting only the distinct ones).

The product of its digits is 11664, while the sum is 36.

The square root of 691938 is about 831.8281072433. The cubic root of 691938 is about 88.4482125436.

The spelling of 691938 in words is "six hundred ninety-one thousand, nine hundred thirty-eight".