221163634404 has 72 divisors (see below), whose sum is σ = 566351909760. Its totient is φ = 72759390912.

The previous prime is 221163634399. The next prime is 221163634423. The reversal of 221163634404 is 404436361122.

221163634404 is a `hidden beast` number, since 2 + 2 + 1 + 16 + 3 + 634 + 4 + 0 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7940767 + ... + 7968569.

Almost surely, 2^221163634404 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 221163634404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (283175954880).

221163634404 is an abundant number, since it is smaller than the sum of its proper divisors (345188275356).

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

221163634404 is a wasteful number, since it uses less digits than its factorization.

221163634404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30689 (or 30684 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 36.

Adding to 221163634404 its reverse (404436361122), we get a palindrome (625599995526).

The spelling of 221163634404 in words is "two hundred twenty-one billion, one hundred sixty-three million, six hundred thirty-four thousand, four hundred four".