21112221001973 has 2 divisors, whose sum is σ = 21112221001974. Its totient is φ = 21112221001972.

The previous prime is 21112221001943. The next prime is 21112221002027. The reversal of 21112221001973 is 37910012221112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20368766633329 + 743454368644 = 4513177^2 + 862238^2 .

It is a cyclic number.

It is not a de Polignac number, because 21112221001973 - 2¹⁶ = 21112220936437 is a prime.

It is a super-2 number, since 2×21112221001973² (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 (21112221001933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556110500986 + 10556110500987.

It is an arithmetic number, because the mean of its divisors is an integer number (10556110500987).

Almost surely, 2^{21112221001973} is an apocalyptic number.

It is an amenable number.

21112221001973 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112221001973 is an equidigital number, since it uses as much as digits as its factorization.

21112221001973 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 32.

The spelling of 21112221001973 in words is "twenty-one trillion, one hundred twelve billion, two hundred twenty-one million, one thousand, nine hundred seventy-three".