405561025985 has 32 divisors (see below), whose sum is σ = 509827681440. Its totient is φ = 309310783488.

The previous prime is 405561025889. The next prime is 405561025993. The reversal of 405561025985 is 589520165504.

It is a happy number.

It can be written as a sum of positive squares in 16 ways, for example, as 192279619009 + 213281406976 = 438497^2 + 461824^2 .

It is a cyclic number.

It is not a de Polignac number, because 405561025985 - 2¹⁸ = 405560763841 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6056849 + ... + 6123441.

It is an arithmetic number, because the mean of its divisors is an integer number (15932115045).

Almost surely, 2^405561025985 is an apocalyptic number.

It is an amenable number.

405561025985 is a deficient number, since it is larger than the sum of its proper divisors (104266655455).

405561025985 is a wasteful number, since it uses less digits than its factorization.

405561025985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67157.

The product of its (nonzero) digits is 2160000, while the sum is 50.

The spelling of 405561025985 in words is "four hundred five billion, five hundred sixty-one million, twenty-five thousand, nine hundred eighty-five".