21112012222001 has 2 divisors, whose sum is σ = 21112012222002. Its totient is φ = 21112012222000.

The previous prime is 21112012221997. The next prime is 21112012222031. The reversal of 21112012222001 is 10022221021112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20272866451600 + 839145770401 = 4502540^2 + 916049^2 .

It is a cyclic number.

It is not a de Polignac number, because 21112012222001 - 2² = 21112012221997 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (21112012222031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556006111000 + 10556006111001.

It is an arithmetic number, because the mean of its divisors is an integer number (10556006111001).

Almost surely, 2^{21112012222001} is an apocalyptic number.

It is an amenable number.

21112012222001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112012222001 is an equidigital number, since it uses as much as digits as its factorization.

21112012222001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21112012222001 its reverse (10022221021112), we get a palindrome (31134233243113).

The spelling of 21112012222001 in words is "twenty-one trillion, one hundred twelve billion, twelve million, two hundred twenty-two thousand, one".