20121202021 has 4 divisors (see below), whose sum is σ = 20154351232. Its totient is φ = 20088052812.

The previous prime is 20121202001. The next prime is 20121202039. The reversal of 20121202021 is 12020212102.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20121202021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20121201992 and 20121202010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121202001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16573695 + ... + 16574908.

It is an arithmetic number, because the mean of its divisors is an integer number (5038587808).

Almost surely, 2^20121202021 is an apocalyptic number.

It is an amenable number.

20121202021 is a deficient number, since it is larger than the sum of its proper divisors (33149211).

20121202021 is an equidigital number, since it uses as much as digits as its factorization.

20121202021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33149210.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 20121202021 its reverse (12020212102), we get a palindrome (32141414123).

The spelling of 20121202021 in words is "twenty billion, one hundred twenty-one million, two hundred two thousand, twenty-one".