21020312103020 has 96 divisors (see below), whose sum is σ = 45855748874880. Its totient is φ = 8084279347200.

The previous prime is 21020312102981. The next prime is 21020312103103. The reversal of 21020312103020 is 2030121302012.

It is a self number, because there is not a number n which added to its sum of digits gives 21020312103020.

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, 289312337 + ... + 289384983.

It is an arithmetic number, because the mean of its divisors is an integer number (477664050780).

Almost surely, 2^{21020312103020} is an apocalyptic number.

21020312103020 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 21020312103020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22927874437440).

21020312103020 is an abundant number, since it is smaller than the sum of its proper divisors (24835436771860).

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

21020312103020 is a wasteful number, since it uses less digits than its factorization.

21020312103020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74763 (or 74761 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21020312103020 its reverse (2030121302012), we get a palindrome (23050433405032).

The spelling of 21020312103020 in words is "twenty-one trillion, twenty billion, three hundred twelve million, one hundred three thousand, twenty".