321121100081 has 2 divisors, whose sum is σ = 321121100082. Its totient is φ = 321121100080.

The previous prime is 321121100063. The next prime is 321121100141. The reversal of 321121100081 is 180001121123.

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., 312974232481 + 8146867600 = 559441^2 + 90260^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-321121100081 is a prime.

It is a super-2 number, since 2×321121100081² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (321121108081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160560550040 + 160560550041.

It is an arithmetic number, because the mean of its divisors is an integer number (160560550041).

Almost surely, 2^321121100081 is an apocalyptic number.

It is an amenable number.

321121100081 is a deficient number, since it is larger than the sum of its proper divisors (1).

321121100081 is an equidigital number, since it uses as much as digits as its factorization.

321121100081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 20.

The spelling of 321121100081 in words is "three hundred twenty-one billion, one hundred twenty-one million, one hundred thousand, eighty-one".