21223061321553 has 48 divisors (see below), whose sum is σ = 37733116861440. Its totient is φ = 11193623425152.

The previous prime is 21223061321503. The next prime is 21223061321557. The reversal of 21223061321553 is 35512316032212.

21223061321553 is a `hidden beast` number, since 2 + 1 + 2 + 2 + 30 + 613 + 2 + 1 + 5 + 5 + 3 = 666.

It is not a de Polignac number, because 21223061321553 - 2²⁶ = 21222994212689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21223061321557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 8514163 + ... + 10720871.

It is an arithmetic number, because the mean of its divisors is an integer number (786106601280).

Almost surely, 2^{21223061321553} is an apocalyptic number.

It is an amenable number.

21223061321553 is a deficient number, since it is larger than the sum of its proper divisors (16510055539887).

21223061321553 is a wasteful number, since it uses less digits than its factorization.

21223061321553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2218478 (or 2218475 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 36.

Adding to 21223061321553 its reverse (35512316032212), we get a palindrome (56735377353765).

The spelling of 21223061321553 in words is "twenty-one trillion, two hundred twenty-three billion, sixty-one million, three hundred twenty-one thousand, five hundred fifty-three".