405641820672 has 320 divisors, whose sum is σ = 1326096731520. Its totient is φ = 122918031360.

The previous prime is 405641820667. The next prime is 405641820679. The reversal of 405641820672 is 276028146504.

405641820672 is a `hidden beast` number, since 4 + 0 + 564 + 1 + 8 + 20 + 67 + 2 = 666.

It is not an unprimeable number, because it can be changed into a prime (405641820679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12300718 + ... + 12333650.

It is an arithmetic number, because the mean of its divisors is an integer number (4144052286).

Almost surely, 2^405641820672 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 405641820672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (663048365760).

405641820672 is an abundant number, since it is smaller than the sum of its proper divisors (920454910848).

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

405641820672 is an frugal number, since it uses more digits than its factorization.

405641820672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32983 (or 32949 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 45.

The spelling of 405641820672 in words is "four hundred five billion, six hundred forty-one million, eight hundred twenty thousand, six hundred seventy-two".