404064640 has 256 divisors, whose sum is σ = 1198540800. Its totient is φ = 127180800.

The previous prime is 404064637. The next prime is 404064641. The reversal of 404064640 is 46460404.

It is a super-3 number, since 3×404064640³ (a number of 27 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 404064599 and 404064608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (404064641) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4000590 + ... + 4000690.

It is an arithmetic number, because the mean of its divisors is an integer number (4681800).

Almost surely, 2^404064640 is an apocalyptic number.

404064640 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 404064640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (599270400).

404064640 is an abundant number, since it is smaller than the sum of its proper divisors (794476160).

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

404064640 is a wasteful number, since it uses less digits than its factorization.

404064640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 193 (or 181 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 28.

The square root of 404064640 is about 20101.3591580271. The cubic root of 404064640 is about 739.2936039583.

It can be divided in two parts, 4040 and 64640, that multiplied together give a square (261145600 = 16160²).

The spelling of 404064640 in words is "four hundred four million, sixty-four thousand, six hundred forty".