10002001021 has 4 divisors (see below), whose sum is σ = 10004549344. Its totient is φ = 9999452700.

The previous prime is 10002001003. The next prime is 10002001027. The reversal of 10002001021 is 12010020001.

10002001021 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 10002001021 - 2⁵ = 10002000989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 10002000995 and 10002001013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10002001027) 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 3 ways as a sum of consecutive naturals, for example, 1268265 + ... + 1276126.

It is an arithmetic number, because the mean of its divisors is an integer number (2501137336).

Almost surely, 2^10002001021 is an apocalyptic number.

It is an amenable number.

10002001021 is a deficient number, since it is larger than the sum of its proper divisors (2548323).

10002001021 is an equidigital number, since it uses as much as digits as its factorization.

10002001021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2548322.

The product of its (nonzero) digits is 4, while the sum is 7.

Adding to 10002001021 its reverse (12010020001), we get a palindrome (22012021022).

The spelling of 10002001021 in words is "ten billion, two million, one thousand, twenty-one".