405806720 has 128 divisors (see below), whose sum is σ = 1077364800. Its totient is φ = 144916480.

The previous prime is 405806717. The next prime is 405806729. The reversal of 405806720 is 27608504.

405806720 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (32).

It is not an unprimeable number, because it can be changed into a prime (405806729) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 414872 + ... + 415848.

Almost surely, 2^405806720 is an apocalyptic number.

405806720 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 405806720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (538682400).

405806720 is an abundant number, since it is smaller than the sum of its proper divisors (671558080).

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

405806720 is a wasteful number, since it uses less digits than its factorization.

405806720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1066 (or 1054 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 32.

The square root of 405806720 is about 20144.6449459900. The cubic root of 405806720 is about 740.3545415766.

The spelling of 405806720 in words is "four hundred five million, eight hundred six thousand, seven hundred twenty".