405444645 has 48 divisors (see below), whose sum is σ = 749314800. Its totient is φ = 202094592.

The previous prime is 405444593. The next prime is 405444649. The reversal of 405444645 is 546444504.

405444645 is a `hidden beast` number, since 4 + 0 + 5 + 4 + 4 + 4 + 645 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 49028004 + 356416641 = 7002^2 + 18879^2 .

It is not a de Polignac number, because 405444645 - 2⁶ = 405444581 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (405444649) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 112207 + ... + 115763.

It is an arithmetic number, because the mean of its divisors is an integer number (15610725).

Almost surely, 2^405444645 is an apocalyptic number.

405444645 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

It is an amenable number.

405444645 is a deficient number, since it is larger than the sum of its proper divisors (343870155).

405444645 is a wasteful number, since it uses less digits than its factorization.

405444645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3734 (or 3731 counting only the distinct ones).

The product of its (nonzero) digits is 153600, while the sum is 36.

The square root of 405444645 is about 20135.6560608290. The cubic root of 405444645 is about 740.1342859538.

The spelling of 405444645 in words is "four hundred five million, four hundred forty-four thousand, six hundred forty-five".