21216043024532 has 6 divisors (see below), whose sum is σ = 37128075292938. Its totient is φ = 10608021512264.

The previous prime is 21216043024511. The next prime is 21216043024537. The reversal of 21216043024532 is 23542034061212.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 19128954279556 + 2087088744976 = 4373666^2 + 1444676^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21216043024492 and 21216043024501.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21216043024537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2652005378063 + ... + 2652005378070.

It is an arithmetic number, because the mean of its divisors is an integer number (6188012548823).

Almost surely, 2^{21216043024532} is an apocalyptic number.

It is an amenable number.

21216043024532 is a deficient number, since it is larger than the sum of its proper divisors (15912032268406).

21216043024532 is a wasteful number, since it uses less digits than its factorization.

21216043024532 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5304010756137 (or 5304010756135 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 35.

Adding to 21216043024532 its reverse (23542034061212), we get a palindrome (44758077085744).

The spelling of 21216043024532 in words is "twenty-one trillion, two hundred sixteen billion, forty-three million, twenty-four thousand, five hundred thirty-two".