210220021 has 8 divisors (see below), whose sum is σ = 236729088. Its totient is φ = 184944000.

The previous prime is 210220019. The next prime is 210220033. The reversal of 210220021 is 120022012.

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

It is a cyclic number.

It is not a de Polignac number, because 210220021 - 2¹ = 210220019 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210220081) 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 7 ways as a sum of consecutive naturals, for example, 307900 + ... + 308581.

It is an arithmetic number, because the mean of its divisors is an integer number (29591136).

Almost surely, 2^210220021 is an apocalyptic number.

It is an amenable number.

210220021 is a deficient number, since it is larger than the sum of its proper divisors (26509067).

210220021 is a wasteful number, since it uses less digits than its factorization.

210220021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 616523.

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 210220021 is about 14498.9662045264. The cubic root of 210220021 is about 594.5997081630.

Adding to 210220021 its reverse (120022012), we get a palindrome (330242033).

The spelling of 210220021 in words is "two hundred ten million, two hundred twenty thousand, twenty-one".