10001221020021 has 48 divisors (see below), whose sum is σ = 16942902677568. Its totient is φ = 5189110617600.

The previous prime is 10001221020013. The next prime is 10001221020023. The reversal of 10001221020021 is 12002012210001.

It is not a de Polignac number, because 10001221020021 - 2³ = 10001221020013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 10001221019979 and 10001221020006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10001221020023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2439220 + ... + 5094333.

It is an arithmetic number, because the mean of its divisors is an integer number (352977139116).

Almost surely, 2^{10001221020021} is an apocalyptic number.

10001221020021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

10001221020021 is a deficient number, since it is larger than the sum of its proper divisors (6941681657547).

10001221020021 is a wasteful number, since it uses less digits than its factorization.

10001221020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7534402 (or 7534395 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 10001221020021 its reverse (12002012210001), we get a palindrome (22003233230022).

The spelling of 10001221020021 in words is "ten trillion, one billion, two hundred twenty-one million, twenty thousand, twenty-one".