21212021121120 has 144 divisors (see below), whose sum is σ = 72393679586592. Its totient is φ = 5655940577280.

The previous prime is 21212021121119. The next prime is 21212021121121. The reversal of 21212021121120 is 2112112021212.

21212021121120 is a `hidden beast` number, since 212 + 12 + 0 + 211 + 211 + 20 = 666.

It is an interprime number because it is at equal distance from previous prime (21212021121119) and next prime (21212021121121).

It is a tau number, because it is divible by the number of its divisors (144).

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 = 21212021121093 and 21212021121102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212021121121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12921444 + ... + 14470236.

It is an arithmetic number, because the mean of its divisors is an integer number (502733886018).

Almost surely, 2^{21212021121120} is an apocalyptic number.

21212021121120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21212021121120 is an abundant number, since it is smaller than the sum of its proper divisors (51181658465472).

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

21212021121120 is a wasteful number, since it uses less digits than its factorization.

21212021121120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1558325 (or 1558314 counting only the distinct ones).

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

Adding to 21212021121120 its reverse (2112112021212), we get a palindrome (23324133142332).

The spelling of 21212021121120 in words is "twenty-one trillion, two hundred twelve billion, twenty-one million, one hundred twenty-one thousand, one hundred twenty".