21621533226053 has 8 divisors (see below), whose sum is σ = 21704908888800. Its totient is φ = 21538179772848.

The previous prime is 21621533226019. The next prime is 21621533226119. The reversal of 21621533226053 is 35062233512612.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21621533226053 - 2¹⁶ = 21621533160517 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21621533226053.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21621533222053) 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 7 ways as a sum of consecutive naturals, for example, 3600263 + ... + 7496996.

It is an arithmetic number, because the mean of its divisors is an integer number (2713113611100).

Almost surely, 2^{21621533226053} is an apocalyptic number.

It is an amenable number.

21621533226053 is a deficient number, since it is larger than the sum of its proper divisors (83375662747).

21621533226053 is a wasteful number, since it uses less digits than its factorization.

21621533226053 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11104771.

The product of its (nonzero) digits is 388800, while the sum is 41.

Adding to 21621533226053 its reverse (35062233512612), we get a palindrome (56683766738665).

The spelling of 21621533226053 in words is "twenty-one trillion, six hundred twenty-one billion, five hundred thirty-three million, two hundred twenty-six thousand, fifty-three".