697644 has 18 divisors (see below), whose sum is σ = 1763580. Its totient is φ = 232536.

The previous prime is 697643. The next prime is 697673. The reversal of 697644 is 446796.

697644 is a `hidden beast` number, since 6 + 9 + 7 + 644 = 666.

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 (36), and also a Moran number because the ratio is a prime number: 19379 = 697644 / (6 + 9 + 7 + 6 + 4 + 4).

It is a nialpdrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 697599 and 697608.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 697644.

It is not an unprimeable number, because it can be changed into a prime (697643) 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, 9654 + ... + 9725.

2⁶⁹⁷⁶⁴⁴ is an apocalyptic number.

It is an amenable number.

697644 is an abundant number, since it is smaller than the sum of its proper divisors (1065936).

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

697644 is a wasteful number, since it uses less digits than its factorization.

697644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19389 (or 19384 counting only the distinct ones).

The product of its digits is 36288, while the sum is 36.

The square root of 697644 is about 835.2508605204. The cubic root of 697644 is about 88.6906738342.

The spelling of 697644 in words is "six hundred ninety-seven thousand, six hundred forty-four".