21533454352404 has 18 divisors (see below), whose sum is σ = 54431787390890. Its totient is φ = 7177818117456.

The previous prime is 21533454352391. The next prime is 21533454352477. The reversal of 21533454352404 is 40425345433512.

21533454352404 is a `hidden beast` number, since 2 + 1 + 53 + 3 + 4 + 543 + 52 + 4 + 0 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 21429029722500 + 104424629904 = 4629150^2 + 323148^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a self number, because there is not a number n which added to its sum of digits gives 21533454352404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 299075754859 + ... + 299075754930.

Almost surely, 2^{21533454352404} is an apocalyptic number.

It is an amenable number.

21533454352404 is an abundant number, since it is smaller than the sum of its proper divisors (32898333038486).

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

21533454352404 is a wasteful number, since it uses less digits than its factorization.

21533454352404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 598151509799 (or 598151509794 counting only the distinct ones).

The product of its (nonzero) digits is 3456000, while the sum is 45.

Adding to 21533454352404 its reverse (40425345433512), we get a palindrome (61958799785916).

The spelling of 21533454352404 in words is "twenty-one trillion, five hundred thirty-three billion, four hundred fifty-four million, three hundred fifty-two thousand, four hundred four".