21227248920 has 64 divisors (see below), whose sum is σ = 64761120000. Its totient is φ = 5564655488.

The previous prime is 21227248879. The next prime is 21227248949. The reversal of 21227248920 is 2984272212.

It is a congruent number.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 1492020 + ... + 1506179.

It is an arithmetic number, because the mean of its divisors is an integer number (1011892500).

Almost surely, 2^21227248920 is an apocalyptic number.

21227248920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21227248920 is an abundant number, since it is smaller than the sum of its proper divisors (43533871080).

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

21227248920 is a wasteful number, since it uses less digits than its factorization.

21227248920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2998272 (or 2998268 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 39.

The spelling of 21227248920 in words is "twenty-one billion, two hundred twenty-seven million, two hundred forty-eight thousand, nine hundred twenty".