210001002020021 has 16 divisors (see below), whose sum is σ = 214651463270400. Its totient is φ = 205400432089008.

The previous prime is 210001002020009. The next prime is 210001002020023. The reversal of 210001002020021 is 120020200100012.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-210001002020021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210001002019984 and 210001002020011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210001002020023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 419551220 + ... + 420051458.

It is an arithmetic number, because the mean of its divisors is an integer number (13415716454400).

Almost surely, 2^{210001002020021} is an apocalyptic number.

It is an amenable number.

210001002020021 is a deficient number, since it is larger than the sum of its proper divisors (4650461250379).

210001002020021 is a wasteful number, since it uses less digits than its factorization.

210001002020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 550088.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 210001002020021 its reverse (120020200100012), we get a palindrome (330021202120033).

The spelling of 210001002020021 in words is "two hundred ten trillion, one billion, two million, twenty thousand, twenty-one".