21289611284 has 6 divisors (see below), whose sum is σ = 37256819754. Its totient is φ = 10644805640.

The previous prime is 21289611199. The next prime is 21289611289. The reversal of 21289611284 is 48211698212.

It can be written as a sum of positive squares in only one way, i.e., 18807379600 + 2482231684 = 137140^2 + 49822^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21289611289) 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, 2661201407 + ... + 2661201414.

It is an arithmetic number, because the mean of its divisors is an integer number (6209469959).

Almost surely, 2^21289611284 is an apocalyptic number.

It is an amenable number.

21289611284 is a deficient number, since it is larger than the sum of its proper divisors (15967208470).

21289611284 is a wasteful number, since it uses less digits than its factorization.

21289611284 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5322402825 (or 5322402823 counting only the distinct ones).

The product of its digits is 110592, while the sum is 44.

The spelling of 21289611284 in words is "twenty-one billion, two hundred eighty-nine million, six hundred eleven thousand, two hundred eighty-four".