1001020100021 has 2 divisors, whose sum is σ = 1001020100022. Its totient is φ = 1001020100020.

The previous prime is 1001020100009. The next prime is 1001020100023. The reversal of 1001020100021 is 1200010201001.

1001020100021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1000978239121 + 41860900 = 1000489^2 + 6470^2 .

It is a cyclic number.

It is not a de Polignac number, because 1001020100021 - 2³⁴ = 983840230837 is a prime.

Together with 1001020100023, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1001020099981 and 1001020100008.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1001020100023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500510050010 + 500510050011.

It is an arithmetic number, because the mean of its divisors is an integer number (500510050011).

Almost surely, 2^{1001020100021} is an apocalyptic number.

It is an amenable number.

1001020100021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001020100021 is an equidigital number, since it uses as much as digits as its factorization.

1001020100021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 1001020100021 its reverse (1200010201001), we get a palindrome (2201030301022).

The spelling of 1001020100021 in words is "one trillion, one billion, twenty million, one hundred thousand, twenty-one".