100021232231981 has 2 divisors, whose sum is σ = 100021232231982. Its totient is φ = 100021232231980.

The previous prime is 100021232231929. The next prime is 100021232232071. The reversal of 100021232231981 is 189132232120001.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64916199729481 + 35105032502500 = 8057059^2 + 5924950^2 .

It is an emirp because it is prime and its reverse (189132232120001) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 100021232231981 - 2⁶ = 100021232231917 is a prime.

It is a super-2 number, since 2×100021232231981² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (100021232231581) 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, 50010616115990 + 50010616115991.

It is an arithmetic number, because the mean of its divisors is an integer number (50010616115991).

Almost surely, 2^{100021232231981} is an apocalyptic number.

It is an amenable number.

100021232231981 is a deficient number, since it is larger than the sum of its proper divisors (1).

100021232231981 is an equidigital number, since it uses as much as digits as its factorization.

100021232231981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 35.

Adding to 100021232231981 its reverse (189132232120001), we get a palindrome (289153464351982).

The spelling of 100021232231981 in words is "one hundred trillion, twenty-one billion, two hundred thirty-two million, two hundred thirty-one thousand, nine hundred eighty-one".