21225332320516 has 12 divisors (see below), whose sum is σ = 37144475914140. Its totient is φ = 10612624916480.

The previous prime is 21225332320499. The next prime is 21225332320541. The reversal of 21225332320516 is 61502323352212.

It can be written as a sum of positive squares in 2 ways, for example, as 19184137200900 + 2041195119616 = 4379970^2 + 1428704^2 .

It is a super-2 number, since 2×21225332320516² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9138205 + ... + 11223076.

It is an arithmetic number, because the mean of its divisors is an integer number (3095372992845).

Almost surely, 2^{21225332320516} is an apocalyptic number.

It is an amenable number.

21225332320516 is a deficient number, since it is larger than the sum of its proper divisors (15919143593624).

21225332320516 is a wasteful number, since it uses less digits than its factorization.

21225332320516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20621894 (or 20621892 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 37.

Adding to 21225332320516 its reverse (61502323352212), we get a palindrome (82727655672728).

The spelling of 21225332320516 in words is "twenty-one trillion, two hundred twenty-five billion, three hundred thirty-two million, three hundred twenty thousand, five hundred sixteen".