21147835020 has 96 divisors (see below), whose sum is σ = 64814393280. Its totient is φ = 5120271360.

The previous prime is 21147834971. The next prime is 21147835067. The reversal of 21147835020 is 2053874112.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 174655 + ... + 269814.

It is an arithmetic number, because the mean of its divisors is an integer number (675149930).

Almost surely, 2^21147835020 is an apocalyptic number.

21147835020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21147835020 is an abundant number, since it is smaller than the sum of its proper divisors (43666558260).

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

21147835020 is a wasteful number, since it uses less digits than its factorization.

21147835020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 444555 (or 444553 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 33.

The spelling of 21147835020 in words is "twenty-one billion, one hundred forty-seven million, eight hundred thirty-five thousand, twenty".