20021021200 has 60 divisors (see below), whose sum is σ = 48124419840. Its totient is φ = 8004426880.

The previous prime is 20021021177. The next prime is 20021021203. The reversal of 20021021200 is 212012002.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is not an unprimeable number, because it can be changed into a prime (20021021203) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 871461 + ... + 894139.

It is an arithmetic number, because the mean of its divisors is an integer number (802073664).

Almost surely, 2^20021021200 is an apocalyptic number.

20021021200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20021021200 is an abundant number, since it is smaller than the sum of its proper divisors (28103398640).

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

20021021200 is a wasteful number, since it uses less digits than its factorization.

20021021200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24904 (or 24893 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 20021021200 its reverse (212012002), we get a palindrome (20233033202).

The spelling of 20021021200 in words is "twenty billion, twenty-one million, twenty-one thousand, two hundred".