689221656 has 128 divisors (see below), whose sum is σ = 2085120000. Its totient is φ = 210107520.

The previous prime is 689221649. The next prime is 689221669. The reversal of 689221656 is 656122986.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 116121 + ... + 121911.

It is an arithmetic number, because the mean of its divisors is an integer number (16290000).

Almost surely, 2^689221656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 689221656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1042560000).

689221656 is an abundant number, since it is smaller than the sum of its proper divisors (1395898344).

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

689221656 is a wasteful number, since it uses less digits than its factorization.

689221656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5854 (or 5844 counting only the distinct ones).

The product of its digits is 311040, while the sum is 45.

The square root of 689221656 is about 26253.0313678249. The cubic root of 689221656 is about 883.3232024786.

The spelling of 689221656 in words is "six hundred eighty-nine million, two hundred twenty-one thousand, six hundred fifty-six".