20513221000 has 64 divisors (see below), whose sum is σ = 48269520000. Its totient is φ = 8159377600.

The previous prime is 20513220997. The next prime is 20513221013. The reversal of 20513221000 is 12231502.

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, 121701 + ... + 236299.

It is an arithmetic number, because the mean of its divisors is an integer number (754211250).

Almost surely, 2^20513221000 is an apocalyptic number.

20513221000 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 20513221000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24134760000).

20513221000 is an abundant number, since it is smaller than the sum of its proper divisors (27756299000).

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

20513221000 is a wasteful number, since it uses less digits than its factorization.

20513221000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114799 (or 114785 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 16.

Adding to 20513221000 its reverse (12231502), we get a palindrome (20525452502).

The spelling of 20513221000 in words is "twenty billion, five hundred thirteen million, two hundred twenty-one thousand".