21221101009993 has 2 divisors, whose sum is σ = 21221101009994. Its totient is φ = 21221101009992.

The previous prime is 21221101009981. The next prime is 21221101010027. The reversal of 21221101009993 is 39990010112212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20758120107664 + 462980902329 = 4556108^2 + 680427^2 .

It is a cyclic number.

It is not a de Polignac number, because 21221101009993 - 2¹³ = 21221101001801 is a prime.

It is not a weakly prime, because it can be changed into another prime (21221101006993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610550504996 + 10610550504997.

It is an arithmetic number, because the mean of its divisors is an integer number (10610550504997).

Almost surely, 2^{21221101009993} is an apocalyptic number.

It is an amenable number.

21221101009993 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221101009993 is an equidigital number, since it uses as much as digits as its factorization.

21221101009993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17496, while the sum is 40.

The spelling of 21221101009993 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred one million, nine thousand, nine hundred ninety-three".