656789 has 4 divisors (see below), whose sum is σ = 750624. Its totient is φ = 562956.

The previous prime is 656783. The next prime is 656791. The reversal of 656789 is 987656.

It is a happy number.

656789 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-656789 is a prime.

It is a d-powerful number, because it can be written as 6³ + 5⁷ + 7³ + 6⁶ + 8 + 9⁶ .

It is an alternating number because its digits alternate between even and odd.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (656783) 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, 46907 + ... + 46920.

It is an arithmetic number, because the mean of its divisors is an integer number (187656).

2⁶⁵⁶⁷⁸⁹ is an apocalyptic number.

It is an amenable number.

656789 is a deficient number, since it is larger than the sum of its proper divisors (93835).

656789 is an equidigital number, since it uses as much as digits as its factorization.

656789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93834.

The product of its digits is 90720, while the sum is 41.

The square root of 656789 is about 810.4251970417. The cubic root of 656789 is about 86.9244510828.

The spelling of 656789 in words is "six hundred fifty-six thousand, seven hundred eighty-nine".