821618422272 has 150 divisors (see below), whose sum is σ = 2452865731899. Its totient is φ = 273811276800.

The previous prime is 821618422253. The next prime is 821618422279. The reversal of 821618422272 is 272224816128.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

821618422272 is a `hidden beast` number, since 8 + 2 + 1 + 618 + 4 + 2 + 2 + 27 + 2 = 666.

It can be written as a sum of positive squares in only one way, i.e., 410809211136 + 410809211136 = 640944^2 + 640944^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=640944.

It is not an unprimeable number, because it can be changed into a prime (821618422279) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 184589647 + ... + 184594097.

Almost surely, 2^821618422272 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 821618422272

821618422272 is an abundant number, since it is smaller than the sum of its proper divisors (1631247309627).

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

821618422272 is an frugal number, since it uses more digits than its factorization.

821618422272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8932 (or 4456 counting only the distinct ones).

The product of its digits is 344064, while the sum is 45.

The spelling of 821618422272 in words is "eight hundred twenty-one billion, six hundred eighteen million, four hundred twenty-two thousand, two hundred seventy-two".