20000121021220 has 24 divisors (see below), whose sum is σ = 42006522185208. Its totient is φ = 7998854496000.

The previous prime is 20000121021203. The next prime is 20000121021233. The reversal of 20000121021220 is 2212012100002.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 5583504347136 + 14416616674084 = 2362944^2 + 3796922^2 .

It is a super-2 number, since 2×20000121021220² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20000121021220.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 74482161 + ... + 74750200.

It is an arithmetic number, because the mean of its divisors is an integer number (1750271757717).

Almost surely, 2^{20000121021220} is an apocalyptic number.

20000121021220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20000121021220 is an abundant number, since it is smaller than the sum of its proper divisors (22006401163988).

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

20000121021220 is a wasteful number, since it uses less digits than its factorization.

20000121021220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149239071 (or 149239069 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 20000121021220 its reverse (2212012100002), we get a palindrome (22212133121222).

The spelling of 20000121021220 in words is "twenty trillion, one hundred twenty-one million, twenty-one thousand, two hundred twenty".