202001000021 has 16 divisors (see below), whose sum is σ = 209629751808. Its totient is φ = 194442897600.

The previous prime is 202001000011. The next prime is 202001000029. The reversal of 202001000021 is 120000100202.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-202001000021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 202000999972 and 202001000008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (202001000029) 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, 12269231 + ... + 12285683.

It is an arithmetic number, because the mean of its divisors is an integer number (13101859488).

Almost surely, 2^202001000021 is an apocalyptic number.

It is an amenable number.

202001000021 is a deficient number, since it is larger than the sum of its proper divisors (7628751787).

202001000021 is a wasteful number, since it uses less digits than its factorization.

202001000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18572.

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

Adding to 202001000021 its reverse (120000100202), we get a palindrome (322001100223).

The spelling of 202001000021 in words is "two hundred two billion, one million, twenty-one", and thus it is an aban number.