684674920 has 48 divisors (see below), whose sum is σ = 1595550060. Its totient is φ = 264413184.

The previous prime is 684674873. The next prime is 684674923. The reversal of 684674920 is 29476486.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 266799556 + 417875364 = 16334^2 + 20442^2 .

It is a Smith number, since the sum of its digits (46) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (684674923) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 23464 + ... + 43816.

Almost surely, 2^684674920 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 684674920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (797775030).

684674920 is an abundant number, since it is smaller than the sum of its proper divisors (910875140).

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

684674920 is a wasteful number, since it uses less digits than its factorization.

684674920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20422 (or 20389 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 46.

The square root of 684674920 is about 26166.2935854507. The cubic root of 684674920 is about 881.3765130643.

The spelling of 684674920 in words is "six hundred eighty-four million, six hundred seventy-four thousand, nine hundred twenty".