697639 has 4 divisors (see below), whose sum is σ = 710856. Its totient is φ = 684424.

The previous prime is 697637. The next prime is 697643. The reversal of 697639 is 936796.

697639 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 697639 - 2¹ = 697637 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (697637) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6529 + ... + 6634.

It is an arithmetic number, because the mean of its divisors is an integer number (177714).

2⁶⁹⁷⁶³⁹ is an apocalyptic number.

697639 is a deficient number, since it is larger than the sum of its proper divisors (13217).

697639 is a wasteful number, since it uses less digits than its factorization.

697639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13216.

The product of its digits is 61236, while the sum is 40.

The square root of 697639 is about 835.2478674022. The cubic root of 697639 is about 88.6904619523.

The spelling of 697639 in words is "six hundred ninety-seven thousand, six hundred thirty-nine".