21443253255215 has 16 divisors (see below), whose sum is σ = 28071722295936. Its totient is φ = 15594785277600.

The previous prime is 21443253255169. The next prime is 21443253255239. The reversal of 21443253255215 is 51255235234412.

It is not a de Polignac number, because 21443253255215 - 2²⁸ = 21442984819759 is a prime.

It is a super-2 number, since 2×21443253255215² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 1021097 + ... + 6627906.

It is an arithmetic number, because the mean of its divisors is an integer number (1754482643496).

Almost surely, 2^{21443253255215} is an apocalyptic number.

21443253255215 is a deficient number, since it is larger than the sum of its proper divisors (6628469040721).

21443253255215 is a wasteful number, since it uses less digits than its factorization.

21443253255215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7699990.

The product of its digits is 1440000, while the sum is 44.

Adding to 21443253255215 its reverse (51255235234412), we get a palindrome (72698488489627).

The spelling of 21443253255215 in words is "twenty-one trillion, four hundred forty-three billion, two hundred fifty-three million, two hundred fifty-five thousand, two hundred fifteen".