12121020 has 36 divisors (see below), whose sum is σ = 36767640. Its totient is φ = 3232224.

The previous prime is 12121009. The next prime is 12121061. The reversal of 12121020 is 2012121.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 12120993 and 12121011.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33490 + ... + 33849.

Almost surely, 2^12121020 is an apocalyptic number.

12121020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12121020 is an abundant number, since it is smaller than the sum of its proper divisors (24646620).

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

12121020 is a wasteful number, since it uses less digits than its factorization.

12121020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67354 (or 67349 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 12121020 is about 3481.5255276962. The cubic root of 12121020 is about 229.7099052141.

Adding to 12121020 its reverse (2012121), we get a palindrome (14133141).

The spelling of 12121020 in words is "twelve million, one hundred twenty-one thousand, twenty".