20001210220021 has 4 divisors (see below), whose sum is σ = 20006042601600. Its totient is φ = 19996377838444.

The previous prime is 20001210219997. The next prime is 20001210220027. The reversal of 20001210220021 is 12002201210002.

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-20001210220021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20001210219983 and 20001210220010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20001210220027) 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, 2416184581 + ... + 2416192858.

It is an arithmetic number, because the mean of its divisors is an integer number (5001510650400).

Almost surely, 2^{20001210220021} is an apocalyptic number.

It is an amenable number.

20001210220021 is a deficient number, since it is larger than the sum of its proper divisors (4832381579).

20001210220021 is an equidigital number, since it uses as much as digits as its factorization.

20001210220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4832381578.

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

Adding to 20001210220021 its reverse (12002201210002), we get a palindrome (32003411430023).

The spelling of 20001210220021 in words is "twenty trillion, one billion, two hundred ten million, two hundred twenty thousand, twenty-one".