21220015522016 has 24 divisors (see below), whose sum is σ = 41789948815944. Its totient is φ = 10606695187840.

The previous prime is 21220015521949. The next prime is 21220015522049. The reversal of 21220015522016 is 61022551002212.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21220015522016.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 103413815 + ... + 103618806.

It is an arithmetic number, because the mean of its divisors is an integer number (1741247867331).

Almost surely, 2^{21220015522016} is an apocalyptic number.

It is an amenable number.

21220015522016 is a deficient number, since it is larger than the sum of its proper divisors (20569933293928).

21220015522016 is a wasteful number, since it uses less digits than its factorization.

21220015522016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207035834 (or 207035826 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 29.

Adding to 21220015522016 its reverse (61022551002212), we get a palindrome (82242566524228).

The spelling of 21220015522016 in words is "twenty-one trillion, two hundred twenty billion, fifteen million, five hundred twenty-two thousand, sixteen".