684985920 has 112 divisors (see below), whose sum is σ = 2245083648. Its totient is φ = 176762880.

The previous prime is 684985901. The next prime is 684985927. The reversal of 684985920 is 29589486.

It is not an unprimeable number, because it can be changed into a prime (684985927) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18252 + ... + 41268.

Almost surely, 2^684985920 is an apocalyptic number.

684985920 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 684985920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1122541824).

684985920 is an abundant number, since it is smaller than the sum of its proper divisors (1560097728).

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

684985920 is a wasteful number, since it uses less digits than its factorization.

684985920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23068 (or 23058 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 51.

The square root of 684985920 is about 26172.2356706492. The cubic root of 684985920 is about 881.5099421293.

The spelling of 684985920 in words is "six hundred eighty-four million, nine hundred eighty-five thousand, nine hundred twenty".