405664020 has 72 divisors (see below), whose sum is σ = 1233007776. Its totient is φ = 107957952.

The previous prime is 405664019. The next prime is 405664033. The reversal of 405664020 is 20466504.

It is a happy number.

405664020 is a `hidden beast` number, since 40 + 566 + 40 + 20 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 99339 + ... + 103341.

It is an arithmetic number, because the mean of its divisors is an integer number (17125108).

Almost surely, 2^405664020 is an apocalyptic number.

It is an amenable number.

405664020 is an abundant number, since it is smaller than the sum of its proper divisors (827343756).

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

405664020 is a wasteful number, since it uses less digits than its factorization.

405664020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4581 (or 4576 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 405664020 is about 20141.1027503461. The cubic root of 405664020 is about 740.2677506867.

The spelling of 405664020 in words is "four hundred five million, six hundred sixty-four thousand, twenty".