684542540 has 48 divisors (see below), whose sum is σ = 1577076480. Its totient is φ = 247519680.

The previous prime is 684542533. The next prime is 684542627. The reversal of 684542540 is 45245486.

It is a junction number, because it is equal to n+sod(n) for n = 684542494 and 684542503.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30689 + ... + 48071.

It is an arithmetic number, because the mean of its divisors is an integer number (32855760).

Almost surely, 2^684542540 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 684542540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (788538240).

684542540 is an abundant number, since it is smaller than the sum of its proper divisors (892533940).

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

684542540 is a wasteful number, since it uses less digits than its factorization.

684542540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17582 (or 17580 counting only the distinct ones).

The product of its (nonzero) digits is 153600, while the sum is 38.

The square root of 684542540 is about 26163.7638729599. The cubic root of 684542540 is about 881.3197055001.

The spelling of 684542540 in words is "six hundred eighty-four million, five hundred forty-two thousand, five hundred forty".