10001001210021 has 20 divisors (see below), whose sum is σ = 15304151811564. Its totient is φ = 6504716232000.

The previous prime is 10001001209971. The next prime is 10001001210107. The reversal of 10001001210021 is 12001210010001.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 4355197521921 + 5645803688100 = 2086911^2 + 2376090^2 .

It is not a de Polignac number, because 10001001210021 - 2¹⁰ = 10001001208997 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 10001001209985 and 10001001210012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10001001210821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1505718030 + ... + 1505724671.

Almost surely, 2^{10001001210021} is an apocalyptic number.

It is an amenable number.

10001001210021 is a deficient number, since it is larger than the sum of its proper divisors (5303150601543).

10001001210021 is an equidigital number, since it uses as much as digits as its factorization.

10001001210021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3011442754 (or 3011442745 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 10001001210021 its reverse (12001210010001), we get a palindrome (22002211220022).

The spelling of 10001001210021 in words is "ten trillion, one billion, one million, two hundred ten thousand, twenty-one".