21110121210953 has 2 divisors, whose sum is σ = 21110121210954. Its totient is φ = 21110121210952.

The previous prime is 21110121210821. The next prime is 21110121211097. The reversal of 21110121210953 is 35901212101112.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16782106980409 + 4328014230544 = 4096597^2 + 2080388^2 .

It is a cyclic number.

It is not a de Polignac number, because 21110121210953 - 2³⁸ = 20835243304009 is a prime.

It is a super-2 number, since 2×21110121210953² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21110121210253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555060605476 + 10555060605477.

It is an arithmetic number, because the mean of its divisors is an integer number (10555060605477).

Almost surely, 2^{21110121210953} is an apocalyptic number.

It is an amenable number.

21110121210953 is a deficient number, since it is larger than the sum of its proper divisors (1).

21110121210953 is an equidigital number, since it uses as much as digits as its factorization.

21110121210953 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080, while the sum is 29.

The spelling of 21110121210953 in words is "twenty-one trillion, one hundred ten billion, one hundred twenty-one million, two hundred ten thousand, nine hundred fifty-three".