21015224211044 has 36 divisors (see below), whose sum is σ = 42785500618476. Its totient is φ = 9005575509504.

The previous prime is 21015224211031. The next prime is 21015224211077. The reversal of 21015224211044 is 44011242251012.

It can be written as a sum of positive squares in 2 ways, for example, as 12265685017600 + 8749539193444 = 3502240^2 + 2957962^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21015224210998 and 21015224211016.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3783557 + ... + 7506380.

It is an arithmetic number, because the mean of its divisors is an integer number (1188486128291).

Almost surely, 2^{21015224211044} is an apocalyptic number.

It is an amenable number.

21015224211044 is an abundant number, since it is smaller than the sum of its proper divisors (21770276407432).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21015224211044 is a wasteful number, since it uses less digits than its factorization.

21015224211044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11299452 (or 11299443 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 29.

Adding to 21015224211044 its reverse (44011242251012), we get a palindrome (65026466462056).

The spelling of 21015224211044 in words is "twenty-one trillion, fifteen billion, two hundred twenty-four million, two hundred eleven thousand, forty-four".