20212001212121 has 4 divisors (see below), whose sum is σ = 20258042217600. Its totient is φ = 20165960206644.

The previous prime is 20212001212009. The next prime is 20212001212133. The reversal of 20212001212121 is 12121210021202.

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 not a de Polignac number, because 20212001212121 - 2¹⁰ = 20212001211097 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20212001212121.

It is not an unprimeable number, because it can be changed into a prime (20212001212321) 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, 23020502081 + ... + 23020502958.

It is an arithmetic number, because the mean of its divisors is an integer number (5064510554400).

Almost surely, 2^{20212001212121} is an apocalyptic number.

It is an amenable number.

20212001212121 is a deficient number, since it is larger than the sum of its proper divisors (46041005479).

20212001212121 is an equidigital number, since it uses as much as digits as its factorization.

20212001212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46041005478.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 20212001212121 its reverse (12121210021202), we get a palindrome (32333211233323).

The spelling of 20212001212121 in words is "twenty trillion, two hundred twelve billion, one million, two hundred twelve thousand, one hundred twenty-one".