121211121220020 has 72 divisors (see below), whose sum is σ = 395956329326376. Its totient is φ = 29836583684352.

The previous prime is 121211121219977. The next prime is 121211121220199. The reversal of 121211121220020 is 20022121112121.

121211121220020 is a `hidden beast` number, since 1 + 21 + 211 + 1 + 212 + 200 + 20 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 3790014665616 + 117421106554404 = 1946796^2 + 10836102^2 .

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 = 121211121219975 and 121211121220002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 25899809887 + ... + 25899814566.

Almost surely, 2^{121211121220020} is an apocalyptic number.

121211121220020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121211121220020 is an abundant number, since it is smaller than the sum of its proper divisors (274745208106356).

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

121211121220020 is a wasteful number, since it uses less digits than its factorization.

121211121220020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51799624481 (or 51799624476 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 121211121220020 its reverse (20022121112121), we get a palindrome (141233242332141).

The spelling of 121211121220020 in words is "one hundred twenty-one trillion, two hundred eleven billion, one hundred twenty-one million, two hundred twenty thousand, twenty".