100021221001021 has 4 divisors (see below), whose sum is σ = 100243985413500. Its totient is φ = 99798456588544.

The previous prime is 100021221000989. The next prime is 100021221001087. The reversal of 100021221001021 is 120100122120001.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 60949795491225 + 39071425509796 = 7807035^2 + 6250714^2 .

It is a cyclic number.

It is not a de Polignac number, because 100021221001021 - 2⁵ = 100021221000989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 100021221000992 and 100021221001010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100021221008021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111382205566 + ... + 111382206463.

It is an arithmetic number, because the mean of its divisors is an integer number (25060996353375).

Almost surely, 2^{100021221001021} is an apocalyptic number.

It is an amenable number.

100021221001021 is a deficient number, since it is larger than the sum of its proper divisors (222764412479).

100021221001021 is an equidigital number, since it uses as much as digits as its factorization.

100021221001021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222764412478.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 100021221001021 its reverse (120100122120001), we get a palindrome (220121343121022).

The spelling of 100021221001021 in words is "one hundred trillion, twenty-one billion, two hundred twenty-one million, one thousand, twenty-one".