20121001001220 has 48 divisors (see below), whose sum is σ = 64387203205248. Its totient is φ = 4599085943040.

The previous prime is 20121001001191. The next prime is 20121001001329. The reversal of 20121001001220 is 2210010012102.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 20121001001196 and 20121001001205.

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, 23953572201 + ... + 23953573040.

It is an arithmetic number, because the mean of its divisors is an integer number (1341400066776).

Almost surely, 2^{20121001001220} is an apocalyptic number.

20121001001220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20121001001220 is an abundant number, since it is smaller than the sum of its proper divisors (44266202204028).

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

20121001001220 is a wasteful number, since it uses less digits than its factorization.

20121001001220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47907145260 (or 47907145258 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 20121001001220 its reverse (2210010012102), we get a palindrome (22331011013322).

The spelling of 20121001001220 in words is "twenty trillion, one hundred twenty-one billion, one million, one thousand, two hundred twenty".