221100201220020 has 96 divisors (see below), whose sum is σ = 625283387688960. Its totient is φ = 58369660752000.

The previous prime is 221100201220001. The next prime is 221100201220039. The reversal of 221100201220020 is 20022102001122.

It is an interprime number because it is at equal distance from previous prime (221100201220001) and next prime (221100201220039).

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

It is a congruent number.

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, 14588761 + ... + 25593599.

It is an arithmetic number, because the mean of its divisors is an integer number (6513368621760).

Almost surely, 2^{221100201220020} is an apocalyptic number.

221100201220020 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 221100201220020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (312641693844480).

221100201220020 is an abundant number, since it is smaller than the sum of its proper divisors (404183186468940).

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

221100201220020 is a wasteful number, since it uses less digits than its factorization.

221100201220020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11008205 (or 11008203 counting only the distinct ones).

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

Adding to 221100201220020 its reverse (20022102001122), we get a palindrome (241122303221142).

The spelling of 221100201220020 in words is "two hundred twenty-one trillion, one hundred billion, two hundred one million, two hundred twenty thousand, twenty".