405666020 has 24 divisors (see below), whose sum is σ = 857331384. Its totient is φ = 161231616.

The previous prime is 405666011. The next prime is 405666103. The reversal of 405666020 is 20666504.

405666020 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 13942756 + 391723264 = 3734^2 + 19792^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 61457 + ... + 67736.

It is an arithmetic number, because the mean of its divisors is an integer number (35722141).

Almost surely, 2^405666020 is an apocalyptic number.

It is an amenable number.

405666020 is an abundant number, since it is smaller than the sum of its proper divisors (451665364).

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

405666020 is a wasteful number, since it uses less digits than its factorization.

405666020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129359 (or 129357 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 29.

The square root of 405666020 is about 20141.1523999994. The cubic root of 405666020 is about 740.2689672378.

The spelling of 405666020 in words is "four hundred five million, six hundred sixty-six thousand, twenty".