21303110099981 has 2 divisors, whose sum is σ = 21303110099982. Its totient is φ = 21303110099980.

The previous prime is 21303110099977. The next prime is 21303110100017. The reversal of 21303110099981 is 18999001130312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16906414051081 + 4396696048900 = 4111741^2 + 2096830^2 .

It is a cyclic number.

It is not a de Polignac number, because 21303110099981 - 2² = 21303110099977 is a prime.

It is a super-2 number, since 2×21303110099981² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21303110092981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10651555049990 + 10651555049991.

It is an arithmetic number, because the mean of its divisors is an integer number (10651555049991).

Almost surely, 2^{21303110099981} is an apocalyptic number.

It is an amenable number.

21303110099981 is a deficient number, since it is larger than the sum of its proper divisors (1).

21303110099981 is an equidigital number, since it uses as much as digits as its factorization.

21303110099981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 104976, while the sum is 47.

The spelling of 21303110099981 in words is "twenty-one trillion, three hundred three billion, one hundred ten million, ninety-nine thousand, nine hundred eighty-one".