21324440511 has 16 divisors (see below), whose sum is σ = 34463742720. Its totient is φ = 12923903160.

The previous prime is 21324440507. The next prime is 21324440537. The reversal of 21324440511 is 11504442312.

21324440511 is a `hidden beast` number, since 2 + 1 + 3 + 244 + 405 + 11 = 666.

It is not a de Polignac number, because 21324440511 - 2² = 21324440507 is a prime.

It is a super-2 number, since 2×21324440511² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21324440561) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35899435 + ... + 35900028.

It is an arithmetic number, because the mean of its divisors is an integer number (2153983920).

Almost surely, 2^21324440511 is an apocalyptic number.

21324440511 is a deficient number, since it is larger than the sum of its proper divisors (13139302209).

21324440511 is a wasteful number, since it uses less digits than its factorization.

21324440511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71799483 (or 71799477 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

Adding to 21324440511 its reverse (11504442312), we get a palindrome (32828882823).

The spelling of 21324440511 in words is "twenty-one billion, three hundred twenty-four million, four hundred forty thousand, five hundred eleven".