101211221081 has 2 divisors, whose sum is σ = 101211221082. Its totient is φ = 101211221080.

The previous prime is 101211221057. The next prime is 101211221119. The reversal of 101211221081 is 180122112101.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 94000494025 + 7210727056 = 306595^2 + 84916^2 .

It is a cyclic number.

It is not a de Polignac number, because 101211221081 - 2¹⁰ = 101211220057 is a prime.

It is a super-2 number, since 2×101211221081² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (101211221021) 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, 50605610540 + 50605610541.

It is an arithmetic number, because the mean of its divisors is an integer number (50605610541).

Almost surely, 2^101211221081 is an apocalyptic number.

It is an amenable number.

101211221081 is a deficient number, since it is larger than the sum of its proper divisors (1).

101211221081 is an equidigital number, since it uses as much as digits as its factorization.

101211221081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64, while the sum is 20.

Adding to 101211221081 its reverse (180122112101), we get a palindrome (281333333182).

The spelling of 101211221081 in words is "one hundred one billion, two hundred eleven million, two hundred twenty-one thousand, eighty-one".