210221201021 has 8 divisors (see below), whose sum is σ = 226417207800. Its totient is φ = 194028786432.

The previous prime is 210221200963. The next prime is 210221201027. The reversal of 210221201021 is 120102122012.

It can be written as a sum of positive squares in 4 ways, for example, as 14866924900 + 195354276121 = 121930^2 + 441989^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 210221201021 - 2²² = 210217006717 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210221200987 and 210221201005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210221201027) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 775880 + ... + 1011153.

It is an arithmetic number, because the mean of its divisors is an integer number (28302150975).

Almost surely, 2^210221201021 is an apocalyptic number.

It is an amenable number.

210221201021 is a deficient number, since it is larger than the sum of its proper divisors (16196006779).

210221201021 is a wasteful number, since it uses less digits than its factorization.

210221201021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1796095.

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

Adding to 210221201021 its reverse (120102122012), we get a palindrome (330323323033).

The spelling of 210221201021 in words is "two hundred ten billion, two hundred twenty-one million, two hundred one thousand, twenty-one".