221220201021020 has 48 divisors (see below), whose sum is σ = 467030673238080. Its totient is φ = 88018057506816.

The previous prime is 221220201020993. The next prime is 221220201021047. The reversal of 221220201021020 is 20120102022122.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (221220201020993) and next prime (221220201021047).

It is a self number, because there is not a number n which added to its sum of digits gives 221220201021020.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25735334 + ... + 33237746.

It is an arithmetic number, because the mean of its divisors is an integer number (9729805692460).

Almost surely, 2^{221220201021020} is an apocalyptic number.

221220201021020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221220201021020 is an abundant number, since it is smaller than the sum of its proper divisors (245810472217060).

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

221220201021020 is a wasteful number, since it uses less digits than its factorization.

221220201021020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7510254 (or 7510252 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 221220201021020 its reverse (20120102022122), we get a palindrome (241340303043142).

The spelling of 221220201021020 in words is "two hundred twenty-one trillion, two hundred twenty billion, two hundred one million, twenty-one thousand, twenty".