210001010021 has 16 divisors (see below), whose sum is σ = 231439579776. Its totient is φ = 188955000000.

The previous prime is 210001009997. The next prime is 210001010029. The reversal of 210001010021 is 120010100012.

It is a cyclic number.

It is not a de Polignac number, because 210001010021 - 2⁶ = 210001009957 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210001009990 and 210001010008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210001010029) 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 15 ways as a sum of consecutive naturals, for example, 3369896 + ... + 3431646.

It is an arithmetic number, because the mean of its divisors is an integer number (14464973736).

Almost surely, 2^210001010021 is an apocalyptic number.

It is an amenable number.

210001010021 is a deficient number, since it is larger than the sum of its proper divisors (21438569755).

210001010021 is a wasteful number, since it uses less digits than its factorization.

210001010021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64924.

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 210001010021 its reverse (120010100012), we get a palindrome (330011110033).

The spelling of 210001010021 in words is "two hundred ten billion, one million, ten thousand, twenty-one".