21020878724700 has 144 divisors (see below), whose sum is σ = 63485985136896. Its totient is φ = 5360055360000.

The previous prime is 21020878724647. The next prime is 21020878724749. The reversal of 21020878724700 is 742787802012.

It is a super-3 number, since 3×21020878724700³ (a number of 41 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21020878724700.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 20199319 + ... + 21214481.

It is an arithmetic number, because the mean of its divisors is an integer number (440874896784).

Almost surely, 2^{21020878724700} is an apocalyptic number.

21020878724700 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 21020878724700, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31742992568448).

21020878724700 is an abundant number, since it is smaller than the sum of its proper divisors (42465106412196).

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

21020878724700 is a wasteful number, since it uses less digits than its factorization.

21020878724700 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1018204 (or 1018197 counting only the distinct ones).

The product of its (nonzero) digits is 702464, while the sum is 48.

The spelling of 21020878724700 in words is "twenty-one trillion, twenty billion, eight hundred seventy-eight million, seven hundred twenty-four thousand, seven hundred".