100221212381 has 2 divisors, whose sum is σ = 100221212382. Its totient is φ = 100221212380.

The previous prime is 100221212297. The next prime is 100221212383. The reversal of 100221212381 is 183212122001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64541402500 + 35679809881 = 254050^2 + 188891^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-100221212381 is a prime.

It is a super-2 number, since 2×100221212381² (a number of 23 digits) contains 22 as substring.

Together with 100221212383, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (100221212383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50110606190 + 50110606191.

It is an arithmetic number, because the mean of its divisors is an integer number (50110606191).

Almost surely, 2^100221212381 is an apocalyptic number.

It is an amenable number.

100221212381 is a deficient number, since it is larger than the sum of its proper divisors (1).

100221212381 is an equidigital number, since it uses as much as digits as its factorization.

100221212381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 23.

Adding to 100221212381 its reverse (183212122001), we get a palindrome (283433334382).

The spelling of 100221212381 in words is "one hundred billion, two hundred twenty-one million, two hundred twelve thousand, three hundred eighty-one".