684478784 has 28 divisors (see below), whose sum is σ = 1481742528. Its totient is φ = 311126400.

The previous prime is 684478759. The next prime is 684478787. The reversal of 684478784 is 487874486.

It is a super-2 number, since 2×684478784² = 937022411492237312, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (684478787) 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, 485432 + ... + 486839.

It is an arithmetic number, because the mean of its divisors is an integer number (52919376).

Almost surely, 2^684478784 is an apocalyptic number.

684478784 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

684478784 is an abundant number, since it is smaller than the sum of its proper divisors (797263744).

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

684478784 is a wasteful number, since it uses less digits than its factorization.

684478784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 972294 (or 972284 counting only the distinct ones).

The product of its digits is 9633792, while the sum is 56.

The square root of 684478784 is about 26162.5454419099. The cubic root of 684478784 is about 881.2923435952.

The spelling of 684478784 in words is "six hundred eighty-four million, four hundred seventy-eight thousand, seven hundred eighty-four".