21021101022001 has 2 divisors, whose sum is σ = 21021101022002. Its totient is φ = 21021101022000.

The previous prime is 21021101021939. The next prime is 21021101022067. The reversal of 21021101022001 is 10022010112012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15604198546225 + 5416902475776 = 3950215^2 + 2327424^2 .

It is a cyclic number.

It is not a de Polignac number, because 21021101022001 - 2⁷ = 21021101021873 is a prime.

It is not a weakly prime, because it can be changed into another prime (21021101022091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510550511000 + 10510550511001.

It is an arithmetic number, because the mean of its divisors is an integer number (10510550511001).

Almost surely, 2^{21021101022001} is an apocalyptic number.

It is an amenable number.

21021101022001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21021101022001 is an equidigital number, since it uses as much as digits as its factorization.

21021101022001 is an evil number, because the sum of its binary digits is even.

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

Adding to 21021101022001 its reverse (10022010112012), we get a palindrome (31043111134013).

The spelling of 21021101022001 in words is "twenty-one trillion, twenty-one billion, one hundred one million, twenty-two thousand, one".