21621411353455 has 32 divisors (see below), whose sum is σ = 26230316894208. Its totient is φ = 17108692137600.

The previous prime is 21621411353453. The next prime is 21621411353467. The reversal of 21621411353455 is 55435311412612.

It is not a de Polignac number, because 21621411353455 - 2¹ = 21621411353453 is a prime.

It is a super-3 number, since 3×21621411353455³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21621411353453) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 124187565 + ... + 124361545.

It is an arithmetic number, because the mean of its divisors is an integer number (819697402944).

Almost surely, 2^{21621411353455} is an apocalyptic number.

21621411353455 is a deficient number, since it is larger than the sum of its proper divisors (4608905540753).

21621411353455 is a wasteful number, since it uses less digits than its factorization.

21621411353455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174927.

The product of its digits is 432000, while the sum is 43.

The spelling of 21621411353455 in words is "twenty-one trillion, six hundred twenty-one billion, four hundred eleven million, three hundred fifty-three thousand, four hundred fifty-five".