12121000021 has 8 divisors (see below), whose sum is σ = 13147295840. Its totient is φ = 11108120112.

The previous prime is 12121000009. The next prime is 12121000033. The reversal of 12121000021 is 12000012121.

It is an interprime number because it is at equal distance from previous prime (12121000009) and next prime (12121000033).

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 12121000021 - 2⁹ = 12120999509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12120999971 and 12121000007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12121000321) 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, 3352095 + ... + 3355708.

It is an arithmetic number, because the mean of its divisors is an integer number (1643411980).

Almost surely, 2^12121000021 is an apocalyptic number.

It is an amenable number.

12121000021 is a deficient number, since it is larger than the sum of its proper divisors (1026295819).

12121000021 is a wasteful number, since it uses less digits than its factorization.

12121000021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6707955.

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

Adding to 12121000021 its reverse (12000012121), we get a palindrome (24121012142).

The spelling of 12121000021 in words is "twelve billion, one hundred twenty-one million, twenty-one", and thus it is an aban number.