397684 has 18 divisors (see below), whose sum is σ = 809970. Its totient is φ = 170352.

The previous prime is 397673. The next prime is 397687. The reversal of 397684 is 486793.

397684 is digitally balanced in base 3, 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 only one way, i.e., 396900 + 784 = 630^2 + 28^2 .

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397687) by changing a digit.

397684 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 819 + ... + 1210.

2³⁹⁷⁶⁸⁴ is an apocalyptic number.

It is an amenable number.

397684 is an abundant number, since it is smaller than the sum of its proper divisors (412286).

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

397684 is a wasteful number, since it uses less digits than its factorization.

397684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2047 (or 2038 counting only the distinct ones).

The product of its digits is 36288, while the sum is 37.

The square root of 397684 is about 630.6219152551. The cubic root of 397684 is about 73.5381510177.

It can be divided in two parts, 397 and 684, that added together give a triangular number (1081 = T₄₆).

The spelling of 397684 in words is "three hundred ninety-seven thousand, six hundred eighty-four".