210211220021 has 4 divisors (see below), whose sum is σ = 229321330944. Its totient is φ = 191101109100.

The previous prime is 210211219997. The next prime is 210211220077. The reversal of 210211220021 is 120022112012.

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 210211220021 - 2¹⁴ = 210211203637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210211219978 and 210211220005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210211228021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9555055445 + ... + 9555055466.

It is an arithmetic number, because the mean of its divisors is an integer number (57330332736).

Almost surely, 2^210211220021 is an apocalyptic number.

It is an amenable number.

210211220021 is a deficient number, since it is larger than the sum of its proper divisors (19110110923).

210211220021 is a wasteful number, since it uses less digits than its factorization.

210211220021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19110110922.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 210211220021 its reverse (120022112012), we get a palindrome (330233332033).

The spelling of 210211220021 in words is "two hundred ten billion, two hundred eleven million, two hundred twenty thousand, twenty-one".