21020022101 has 12 divisors (see below), whose sum is σ = 22791065220. Its totient is φ = 19377745920.

The previous prime is 21020022083. The next prime is 21020022103. The reversal of 21020022101 is 10122002012.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 6459979876 + 14560042225 = 80374^2 + 120665^2 .

It is not a de Polignac number, because 21020022101 - 2¹⁴ = 21020005717 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 (21020022103) 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, 49091 + ... + 210831.

It is an arithmetic number, because the mean of its divisors is an integer number (1899255435).

Almost surely, 2^21020022101 is an apocalyptic number.

It is an amenable number.

21020022101 is a deficient number, since it is larger than the sum of its proper divisors (1771043119).

21020022101 is a wasteful number, since it uses less digits than its factorization.

21020022101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162536 (or 162523 counting only the distinct ones).

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

Adding to 21020022101 its reverse (10122002012), we get a palindrome (31142024113).

The spelling of 21020022101 in words is "twenty-one billion, twenty million, twenty-two thousand, one hundred one".