405378720 has 144 divisors (see below), whose sum is σ = 1391349960. Its totient is φ = 107476992.

The previous prime is 405378683. The next prime is 405378731. The reversal of 405378720 is 27873504.

405378720 is a `hidden beast` number, since 40 + 537 + 87 + 2 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 342842256 + 62536464 = 18516^2 + 7908^2 .

It is a tau number, because it is divible by the number of its divisors (144).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 282966 + ... + 284394.

Almost surely, 2^405378720 is an apocalyptic number.

405378720 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 405378720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (695674980).

405378720 is an abundant number, since it is smaller than the sum of its proper divisors (985971240).

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

405378720 is a wasteful number, since it uses less digits than its factorization.

405378720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1647 (or 1636 counting only the distinct ones).

The product of its (nonzero) digits is 47040, while the sum is 36.

The square root of 405378720 is about 20134.0189728728. The cubic root of 405378720 is about 740.0941686832.

The spelling of 405378720 in words is "four hundred five million, three hundred seventy-eight thousand, seven hundred twenty".