1684780640 has 24 divisors (see below), whose sum is σ = 3980294640. Its totient is φ = 673912192.

The previous prime is 1684780621. The next prime is 1684780649. The reversal of 1684780640 is 460874861.

It is a junction number, because it is equal to n+sod(n) for n = 1684780591 and 1684780600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1684780649) 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, 5264780 + ... + 5265099.

It is an arithmetic number, because the mean of its divisors is an integer number (165845610).

Almost surely, 2^1684780640 is an apocalyptic number.

1684780640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1684780640 is an abundant number, since it is smaller than the sum of its proper divisors (2295514000).

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

1684780640 is a wasteful number, since it uses less digits than its factorization.

1684780640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10529894 (or 10529886 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 44.

The square root of 1684780640 is about 41046.0794717352. The cubic root of 1684780640 is about 1189.9109318267.

The spelling of 1684780640 in words is "one billion, six hundred eighty-four million, seven hundred eighty thousand, six hundred forty".