210021200010021 has 4 divisors (see below), whose sum is σ = 280028266680032. Its totient is φ = 140014133340012.

The previous prime is 210021200009953. The next prime is 210021200010047. The reversal of 210021200010021 is 120010002120012.

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 not a de Polignac number, because 210021200010021 - 2²⁹ = 210020663139109 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210021200009979 and 210021200010006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210021200012021) 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, 35003533335001 + ... + 35003533335006.

It is an arithmetic number, because the mean of its divisors is an integer number (70007066670008).

Almost surely, 2^{210021200010021} is an apocalyptic number.

It is an amenable number.

210021200010021 is a deficient number, since it is larger than the sum of its proper divisors (70007066670011).

210021200010021 is an equidigital number, since it uses as much as digits as its factorization.

210021200010021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70007066670010.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 210021200010021 its reverse (120010002120012), we get a palindrome (330031202130033).

The spelling of 210021200010021 in words is "two hundred ten trillion, twenty-one billion, two hundred million, ten thousand, twenty-one".