21544012204 has 48 divisors (see below), whose sum is σ = 44307728640. Its totient is φ = 9036498240.

The previous prime is 21544012199. The next prime is 21544012267. The reversal of 21544012204 is 40221044512.

It is a super-2 number, since 2×21544012204² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3384777 + ... + 3391135.

It is an arithmetic number, because the mean of its divisors is an integer number (923077680).

Almost surely, 2^21544012204 is an apocalyptic number.

It is an amenable number.

21544012204 is an abundant number, since it is smaller than the sum of its proper divisors (22763716436).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21544012204 is a wasteful number, since it uses less digits than its factorization.

21544012204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12310 (or 12308 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 25.

Adding to 21544012204 its reverse (40221044512), we get a palindrome (61765056716).

The spelling of 21544012204 in words is "twenty-one billion, five hundred forty-four million, twelve thousand, two hundred four".