21000002022101 has 4 divisors (see below), whose sum is σ = 21002227315212. Its totient is φ = 20997776728992.

The previous prime is 21000002022059. The next prime is 21000002022143. The reversal of 21000002022101 is 10122020000012.

It is a happy number.

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

It is an interprime number because it is at equal distance from previous prime (21000002022059) and next prime (21000002022143).

It can be written as a sum of positive squares in 2 ways, for example, as 7088959500100 + 13911042522001 = 2662510^2 + 3729751^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21000002022101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000002022191) 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, 1112632400 + ... + 1112651273.

It is an arithmetic number, because the mean of its divisors is an integer number (5250556828803).

Almost surely, 2^{21000002022101} is an apocalyptic number.

It is an amenable number.

21000002022101 is a deficient number, since it is larger than the sum of its proper divisors (2225293111).

21000002022101 is an equidigital number, since it uses as much as digits as its factorization.

21000002022101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2225293110.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21000002022101 its reverse (10122020000012), we get a palindrome (31122022022113).

The spelling of 21000002022101 in words is "twenty-one trillion, two million, twenty-two thousand, one hundred one".