21100243210979 has 2 divisors, whose sum is σ = 21100243210980. Its totient is φ = 21100243210978.

The previous prime is 21100243210939. The next prime is 21100243211101. The reversal of 21100243210979 is 97901234200112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21100243210979 - 2²⁰ = 21100242162403 is a prime.

It is a super-2 number, since 2×21100243210979² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21100243210919) 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, 10550121605489 + 10550121605490.

It is an arithmetic number, because the mean of its divisors is an integer number (10550121605490).

Almost surely, 2^{21100243210979} is an apocalyptic number.

21100243210979 is a deficient number, since it is larger than the sum of its proper divisors (1).

21100243210979 is an equidigital number, since it uses as much as digits as its factorization.

21100243210979 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 54432, while the sum is 41.

The spelling of 21100243210979 in words is "twenty-one trillion, one hundred billion, two hundred forty-three million, two hundred ten thousand, nine hundred seventy-nine".