121121210221020 has 72 divisors (see below), whose sum is σ = 367403484005376. Its totient is φ = 32298771399552.

The previous prime is 121121210220971. The next prime is 121121210221051. The reversal of 121121210221020 is 20122012121121.

121121210221020 is a `hidden beast` number, since 1 + 211 + 2 + 1 + 210 + 221 + 0 + 20 = 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 = 121121210220984 and 121121210221002.

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, 25407654 + ... + 29795826.

Almost surely, 2^{121121210221020} is an apocalyptic number.

121121210221020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121121210221020 is an abundant number, since it is smaller than the sum of its proper divisors (246282273784356).

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

121121210221020 is a wasteful number, since it uses less digits than its factorization.

121121210221020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4541531 (or 4541526 counting only the distinct ones).

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

Adding to 121121210221020 its reverse (20122012121121), we get a palindrome (141243222342141).

The spelling of 121121210221020 in words is "one hundred twenty-one trillion, one hundred twenty-one billion, two hundred ten million, two hundred twenty-one thousand, twenty".