20012121221220 has 96 divisors (see below), whose sum is σ = 62358602423040. Its totient is φ = 5328108253440.

The previous prime is 20012121221179. The next prime is 20012121221227. The reversal of 20012121221220 is 2212212121002.

It is a happy number.

20012121221220 is a `hidden beast` number, since 200 + 1 + 2 + 1 + 21 + 221 + 220 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 20012121221193 and 20012121221202.

It is not an unprimeable number, because it can be changed into a prime (20012121221227) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 29024937 + ... + 29706416.

It is an arithmetic number, because the mean of its divisors is an integer number (649568775240).

Almost surely, 2^{20012121221220} is an apocalyptic number.

20012121221220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20012121221220 is an abundant number, since it is smaller than the sum of its proper divisors (42346481201820).

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

20012121221220 is a wasteful number, since it uses less digits than its factorization.

20012121221220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58732002 (or 58731994 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 20012121221220 its reverse (2212212121002), we get a palindrome (22224333342222).

The spelling of 20012121221220 in words is "twenty trillion, twelve billion, one hundred twenty-one million, two hundred twenty-one thousand, two hundred twenty".