684400860 has 192 divisors, whose sum is σ = 2501775360. Its totient is φ = 153135360.

The previous prime is 684400859. The next prime is 684400861. The reversal of 684400860 is 68004486.

It is an interprime number because it is at equal distance from previous prime (684400859) and next prime (684400861).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (684400861) by changing a digit.

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 63 ways as a sum of consecutive naturals, for example, 72789 + ... + 81651.

It is an arithmetic number, because the mean of its divisors is an integer number (13030080).

Almost surely, 2^684400860 is an apocalyptic number.

684400860 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 684400860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1250887680).

684400860 is an abundant number, since it is smaller than the sum of its proper divisors (1817374500).

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

684400860 is a wasteful number, since it uses less digits than its factorization.

684400860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8905 (or 8897 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 684400860 is about 26161.0561713399. The cubic root of 684400860 is about 881.2588989595.

The spelling of 684400860 in words is "six hundred eighty-four million, four hundred thousand, eight hundred sixty".