21288947484 has 36 divisors (see below), whose sum is σ = 57784287624. Its totient is φ = 6082556256.

The previous prime is 21288947447. The next prime is 21288947489. The reversal of 21288947484 is 48474988212.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21288947489) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18102259 + ... + 18103434.

Almost surely, 2^21288947484 is an apocalyptic number.

It is an amenable number.

21288947484 is an abundant number, since it is smaller than the sum of its proper divisors (36495340140).

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

21288947484 is a wasteful number, since it uses less digits than its factorization.

21288947484 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36205714 (or 36205705 counting only the distinct ones).

The product of its digits is 8257536, while the sum is 57.

The spelling of 21288947484 in words is "twenty-one billion, two hundred eighty-eight million, nine hundred forty-seven thousand, four hundred eighty-four".