405921609 has 6 divisors (see below), whose sum is σ = 586331226. Its totient is φ = 270614400.

The previous prime is 405921601. The next prime is 405921629. The reversal of 405921609 is 906129504.

405921609 is a `hidden beast` number, since 4 + 0 + 592 + 1 + 60 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 318087225 + 87834384 = 17835^2 + 9372^2 .

It is not a de Polignac number, because 405921609 - 2³ = 405921601 is a prime.

It is not an unprimeable number, because it can be changed into a prime (405921601) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 22551192 + ... + 22551209.

It is an arithmetic number, because the mean of its divisors is an integer number (97721871).

Almost surely, 2^405921609 is an apocalyptic number.

It is an amenable number.

405921609 is a deficient number, since it is larger than the sum of its proper divisors (180409617).

405921609 is a wasteful number, since it uses less digits than its factorization.

405921609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45102407 (or 45102404 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The square root of 405921609 is about 20147.4963457001. The cubic root of 405921609 is about 740.4244028865.

The spelling of 405921609 in words is "four hundred five million, nine hundred twenty-one thousand, six hundred nine".