684369840 has 320 divisors, whose sum is σ = 2738396160. Its totient is φ = 137195520.

The previous prime is 684369821. The next prime is 684369859. The reversal of 684369840 is 48963486.

It is an interprime number because it is at equal distance from previous prime (684369821) and next prime (684369859).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 684369840.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 535282 + ... + 536558.

It is an arithmetic number, because the mean of its divisors is an integer number (8557488).

Almost surely, 2^684369840 is an apocalyptic number.

684369840 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 684369840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1369198080).

684369840 is an abundant number, since it is smaller than the sum of its proper divisors (2054026320).

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

684369840 is a wasteful number, since it uses less digits than its factorization.

684369840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1340 (or 1334 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 48.

The square root of 684369840 is about 26160.4632986497. The cubic root of 684369840 is about 881.2455846064.

The spelling of 684369840 in words is "six hundred eighty-four million, three hundred sixty-nine thousand, eight hundred forty".