21020011122001 has 2 divisors, whose sum is σ = 21020011122002. Its totient is φ = 21020011122000.

The previous prime is 21020011121957. The next prime is 21020011122013. The reversal of 21020011122001 is 10022111002012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18790066232001 + 2229944890000 = 4334751^2 + 1493300^2 .

It is a cyclic number.

It is not a de Polignac number, because 21020011122001 - 2⁹ = 21020011121489 is a prime.

It is not a weakly prime, because it can be changed into another prime (21020011122091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510005561000 + 10510005561001.

It is an arithmetic number, because the mean of its divisors is an integer number (10510005561001).

Almost surely, 2^{21020011122001} is an apocalyptic number.

It is an amenable number.

21020011122001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020011122001 is an equidigital number, since it uses as much as digits as its factorization.

21020011122001 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 21020011122001 its reverse (10022111002012), we get a palindrome (31042122124013).

The spelling of 21020011122001 in words is "twenty-one trillion, twenty billion, eleven million, one hundred twenty-two thousand, one".