404684640 has 192 divisors, whose sum is σ = 1430654400. Its totient is φ = 106831872.

The previous prime is 404684639. The next prime is 404684659. The reversal of 404684640 is 46486404.

404684640 is a `hidden beast` number, since 4 + 0 + 4 + 6 + 8 + 4 + 640 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 404684595 and 404684604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 487746 + ... + 488574.

It is an arithmetic number, because the mean of its divisors is an integer number (7451325).

Almost surely, 2^404684640 is an apocalyptic number.

404684640 is a gapful number since it is divisible by the number (40) 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 404684640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (715327200).

404684640 is an abundant number, since it is smaller than the sum of its proper divisors (1025969760).

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

404684640 is a wasteful number, since it uses less digits than its factorization.

404684640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 966 (or 952 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 36.

The square root of 404684640 is about 20116.7750894620. The cubic root of 404684640 is about 739.6715367201.

The spelling of 404684640 in words is "four hundred four million, six hundred eighty-four thousand, six hundred forty".