21443021510055 has 24 divisors (see below), whose sum is σ = 34828549548912. Its totient is φ = 11265587384832.

The previous prime is 21443021510047. The next prime is 21443021510059. The reversal of 21443021510055 is 55001512034412.

It is not a de Polignac number, because 21443021510055 - 2³ = 21443021510047 is a prime.

It is a super-2 number, since 2×21443021510055² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21443021509998 and 21443021510025.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21443021510059) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 159159082 + ... + 159293751.

It is an arithmetic number, because the mean of its divisors is an integer number (1451189564538).

Almost surely, 2^{21443021510055} is an apocalyptic number.

21443021510055 is a deficient number, since it is larger than the sum of its proper divisors (13385528038857).

21443021510055 is an equidigital number, since it uses as much as digits as its factorization.

21443021510055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 318452975 (or 318452908 counting only the distinct ones).

The product of its (nonzero) digits is 24000, while the sum is 33.

Adding to 21443021510055 its reverse (55001512034412), we get a palindrome (76444533544467).

The spelling of 21443021510055 in words is "twenty-one trillion, four hundred forty-three billion, twenty-one million, five hundred ten thousand, fifty-five".