21022101112081 has 2 divisors, whose sum is σ = 21022101112082. Its totient is φ = 21022101112080.

The previous prime is 21022101112079. The next prime is 21022101112087. The reversal of 21022101112081 is 18021110122012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18189329361025 + 2832771751056 = 4264895^2 + 1683084^2 .

It is a cyclic number.

It is not a de Polignac number, because 21022101112081 - 2¹ = 21022101112079 is a prime.

It is a super-2 number, since 2×21022101112081² (a number of 27 digits) contains 22 as substring.

Together with 21022101112079, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21022101112087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10511050556040 + 10511050556041.

It is an arithmetic number, because the mean of its divisors is an integer number (10511050556041).

Almost surely, 2^{21022101112081} is an apocalyptic number.

It is an amenable number.

21022101112081 is a deficient number, since it is larger than the sum of its proper divisors (1).

21022101112081 is an equidigital number, since it uses as much as digits as its factorization.

21022101112081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 22.

Adding to 21022101112081 its reverse (18021110122012), we get a palindrome (39043211234093).

The spelling of 21022101112081 in words is "twenty-one trillion, twenty-two billion, one hundred one million, one hundred twelve thousand, eighty-one".