121765400017 has 2 divisors, whose sum is σ = 121765400018. Its totient is φ = 121765400016.

The previous prime is 121765400011. The next prime is 121765400033. The reversal of 121765400017 is 710004567121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 121636327696 + 129072321 = 348764^2 + 11361^2 .

It is an emirp because it is prime and its reverse (710004567121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121765400017 - 2¹¹ = 121765397969 is a prime.

It is not a weakly prime, because it can be changed into another prime (121765400011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60882700008 + 60882700009.

It is an arithmetic number, because the mean of its divisors is an integer number (60882700009).

Almost surely, 2^121765400017 is an apocalyptic number.

It is an amenable number.

121765400017 is a deficient number, since it is larger than the sum of its proper divisors (1).

121765400017 is an equidigital number, since it uses as much as digits as its factorization.

121765400017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11760, while the sum is 34.

Adding to 121765400017 its reverse (710004567121), we get a palindrome (831769967138).

The spelling of 121765400017 in words is "one hundred twenty-one billion, seven hundred sixty-five million, four hundred thousand, seventeen".