689523840 has 320 divisors, whose sum is σ = 2523692160. Its totient is φ = 179324928.

The previous prime is 689523829. The next prime is 689523881. The reversal of 689523840 is 48325986.

689523840 is a `hidden beast` number, since 6 + 89 + 523 + 8 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (320).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 2436339 + ... + 2436621.

It is an arithmetic number, because the mean of its divisors is an integer number (7886538).

Almost surely, 2^689523840 is an apocalyptic number.

689523840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 689523840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1261846080).

689523840 is an abundant number, since it is smaller than the sum of its proper divisors (1834168320).

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

689523840 is a wasteful number, since it uses less digits than its factorization.

689523840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 361 (or 340 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 45.

The square root of 689523840 is about 26258.7859582274. The cubic root of 689523840 is about 883.4522790658.

The spelling of 689523840 in words is "six hundred eighty-nine million, five hundred twenty-three thousand, eight hundred forty".