21170272000 has 144 divisors (see below), whose sum is σ = 54441563904. Its totient is φ = 8194560000.

The previous prime is 21170271931. The next prime is 21170272051. The reversal of 21170272000 is 27207112.

It is a hoax number, since the sum of its digits (22) coincides with the sum of the digits of its distinct prime factors.

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, 981330 + ... + 1002670.

It is an arithmetic number, because the mean of its divisors is an integer number (378066416).

Almost surely, 2^21170272000 is an apocalyptic number.

21170272000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21170272000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27220781952).

21170272000 is an abundant number, since it is smaller than the sum of its proper divisors (33271291904).

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

21170272000 is an equidigital number, since it uses as much as digits as its factorization.

21170272000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21403 (or 21379 counting only the distinct ones).

The product of its (nonzero) digits is 392, while the sum is 22.

Adding to 21170272000 its reverse (27207112), we get a palindrome (21197479112).

The spelling of 21170272000 in words is "twenty-one billion, one hundred seventy million, two hundred seventy-two thousand".