21111023201 has 2 divisors, whose sum is σ = 21111023202. Its totient is φ = 21111023200.

The previous prime is 21111023173. The next prime is 21111023207. The reversal of 21111023201 is 10232011112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20923333201 + 187690000 = 144649^2 + 13700^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21111023201 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 (21111023207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555511600 + 10555511601.

It is an arithmetic number, because the mean of its divisors is an integer number (10555511601).

Almost surely, 2^21111023201 is an apocalyptic number.

It is an amenable number.

21111023201 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111023201 is an equidigital number, since it uses as much as digits as its factorization.

21111023201 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 21111023201 its reverse (10232011112), we get a palindrome (31343034313).

The spelling of 21111023201 in words is "twenty-one billion, one hundred eleven million, twenty-three thousand, two hundred one".