20123221323220 has 24 divisors (see below), whose sum is σ = 42259264878600. Its totient is φ = 8049193272192.

The previous prime is 20123221323133. The next prime is 20123221323223. The reversal of 20123221323220 is 2232312232102.

It can be written as a sum of positive squares in 4 ways, for example, as 5010067469124 + 15113153854096 = 2238318^2 + 3887564^2 .

It is a super-2 number, since 2×20123221323220² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20123221323223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4208835 + ... + 7613194.

It is an arithmetic number, because the mean of its divisors is an integer number (1760802703275).

Almost surely, 2^{20123221323220} is an apocalyptic number.

20123221323220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20123221323220 is an abundant number, since it is smaller than the sum of its proper divisors (22136043555380).

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

20123221323220 is a wasteful number, since it uses less digits than its factorization.

20123221323220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11907147 (or 11907145 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 25.

Adding to 20123221323220 its reverse (2232312232102), we get a palindrome (22355533555322).

The spelling of 20123221323220 in words is "twenty trillion, one hundred twenty-three billion, two hundred twenty-one million, three hundred twenty-three thousand, two hundred twenty".