1000001020021 has 16 divisors (see below), whose sum is σ = 1087301864880. Its totient is φ = 915976581120.

The previous prime is 1000001020003. The next prime is 1000001020043. The reversal of 1000001020021 is 1200201000001.

It can be written as a sum of positive squares in 8 ways, for example, as 163388957796 + 836612062225 = 404214^2 + 914665^2 .

It is not a de Polignac number, because 1000001020021 - 2¹¹ = 1000001017973 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1000001019986 and 1000001020013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1000001024021) 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 15 ways as a sum of consecutive naturals, for example, 1468866 + ... + 2039011.

It is an arithmetic number, because the mean of its divisors is an integer number (67956366555).

Almost surely, 2^{1000001020021} is an apocalyptic number.

It is an amenable number.

1000001020021 is a deficient number, since it is larger than the sum of its proper divisors (87300844859).

1000001020021 is a wasteful number, since it uses less digits than its factorization.

1000001020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3508344.

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

Adding to 1000001020021 its reverse (1200201000001), we get a palindrome (2200202020022).

The spelling of 1000001020021 in words is "one trillion, one million, twenty thousand, twenty-one".