1001002121021 has 12 divisors (see below), whose sum is σ = 1207382062752. Its totient is φ = 812843825544.

The previous prime is 1001002121011. The next prime is 1001002121071. The reversal of 1001002121021 is 1201212001001.

It is not a de Polignac number, because 1001002121021 - 2³⁴ = 983822251837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1001002120993 and 1001002121011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001002121011) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 198058835 + ... + 198063888.

It is an arithmetic number, because the mean of its divisors is an integer number (100615171896).

Almost surely, 2^{1001002121021} is an apocalyptic number.

It is an amenable number.

1001002121021 is a deficient number, since it is larger than the sum of its proper divisors (206379941731).

1001002121021 is an equidigital number, since it uses as much as digits as its factorization.

1001002121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396122768 (or 396122749 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 1001002121021 its reverse (1201212001001), we get a palindrome (2202214122022).

The spelling of 1001002121021 in words is "one trillion, one billion, two million, one hundred twenty-one thousand, twenty-one".