21216352024431 has 48 divisors (see below), whose sum is σ = 33629084436480. Its totient is φ = 12839157720000.

The previous prime is 21216352024409. The next prime is 21216352024433. The reversal of 21216352024431 is 13442025361212.

It is a happy number.

21216352024431 is a `hidden beast` number, since 2 + 1 + 2 + 1 + 6 + 3 + 5 + 202 + 443 + 1 = 666.

It is not a de Polignac number, because 21216352024431 - 2⁷ = 21216352024303 is a prime.

It is a super-2 number, since 2×21216352024431² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21216352024433) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 19278115 + ... + 20348916.

It is an arithmetic number, because the mean of its divisors is an integer number (700605925760).

Almost surely, 2^{21216352024431} is an apocalyptic number.

21216352024431 is a deficient number, since it is larger than the sum of its proper divisors (12412732412049).

21216352024431 is a wasteful number, since it uses less digits than its factorization.

21216352024431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39627188 (or 39627185 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

Adding to 21216352024431 its reverse (13442025361212), we get a palindrome (34658377385643).

The spelling of 21216352024431 in words is "twenty-one trillion, two hundred sixteen billion, three hundred fifty-two million, twenty-four thousand, four hundred thirty-one".