21121121020001 has 2 divisors, whose sum is σ = 21121121020002. Its totient is φ = 21121121020000.

The previous prime is 21121121019979. The next prime is 21121121020019. The reversal of 21121121020001 is 10002012112112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14103517366225 + 7017603653776 = 3755465^2 + 2649076^2 .

It is a cyclic number.

It is not a de Polignac number, because 21121121020001 - 2⁶ = 21121121019937 is a prime.

It is a super-2 number, since 2×21121121020001² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21121121520001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560560510000 + 10560560510001.

It is an arithmetic number, because the mean of its divisors is an integer number (10560560510001).

Almost surely, 2^{21121121020001} is an apocalyptic number.

It is an amenable number.

21121121020001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21121121020001 is an equidigital number, since it uses as much as digits as its factorization.

21121121020001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21121121020001 its reverse (10002012112112), we get a palindrome (31123133132113).

The spelling of 21121121020001 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred twenty-one million, twenty thousand, one".