21120001202220 has 48 divisors (see below), whose sum is σ = 59178824744928. Its totient is φ = 5627922094080.

The previous prime is 21120001202203. The next prime is 21120001202227. The reversal of 21120001202220 is 2220210002112.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21120001202220.

It is not an unprimeable number, because it can be changed into a prime (21120001202227) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 127361029 + ... + 127526748.

It is an arithmetic number, because the mean of its divisors is an integer number (1232892182186).

Almost surely, 2^{21120001202220} is an apocalyptic number.

21120001202220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21120001202220 is an abundant number, since it is smaller than the sum of its proper divisors (38058823542708).

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

21120001202220 is a wasteful number, since it uses less digits than its factorization.

21120001202220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254889170 (or 254889168 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21120001202220 its reverse (2220210002112), we get a palindrome (23340211204332).

The spelling of 21120001202220 in words is "twenty-one trillion, one hundred twenty billion, one million, two hundred two thousand, two hundred twenty".