21213044024 has 8 divisors (see below), whose sum is σ = 39774457560. Its totient is φ = 10606522008.

The previous prime is 21213044009. The next prime is 21213044029. The reversal of 21213044024 is 42044031212.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×21213044024² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21213044029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1325815244 + ... + 1325815259.

It is an arithmetic number, because the mean of its divisors is an integer number (4971807195).

Almost surely, 2^21213044024 is an apocalyptic number.

It is an amenable number.

21213044024 is a deficient number, since it is larger than the sum of its proper divisors (18561413536).

21213044024 is a wasteful number, since it uses less digits than its factorization.

21213044024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2651630509 (or 2651630505 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 23.

Adding to 21213044024 its reverse (42044031212), we get a palindrome (63257075236).

The spelling of 21213044024 in words is "twenty-one billion, two hundred thirteen million, forty-four thousand, twenty-four".