12121021 has 8 divisors (see below), whose sum is σ = 13248288. Its totient is φ = 10998000.

The previous prime is 12121009. The next prime is 12121061. The reversal of 12121021 is 12012121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12121021 - 2⁵ = 12120989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12120989 and 12121007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12121061) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9766 + ... + 10936.

It is an arithmetic number, because the mean of its divisors is an integer number (1656036).

Almost surely, 2^12121021 is an apocalyptic number.

12121021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12121021 is a deficient number, since it is larger than the sum of its proper divisors (1127267).

12121021 is a wasteful number, since it uses less digits than its factorization.

12121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2123.

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 12121021 is about 3481.5256713114. The cubic root of 12121021 is about 229.7099115312.

Adding to 12121021 its reverse (12012121), we get a palindrome (24133142).

Subtracting from 12121021 its reverse (12012121), we obtain a square (108900 = 330²).

The spelling of 12121021 in words is "twelve million, one hundred twenty-one thousand, twenty-one".