121595501917 has 2 divisors, whose sum is σ = 121595501918. Its totient is φ = 121595501916.

The previous prime is 121595501801. The next prime is 121595501971. The reversal of 121595501917 is 719105595121.

Together with next prime (121595501971) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 110709918361 + 10885583556 = 332731^2 + 104334^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121595501917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121595501017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60797750958 + 60797750959.

It is an arithmetic number, because the mean of its divisors is an integer number (60797750959).

Almost surely, 2^121595501917 is an apocalyptic number.

It is an amenable number.

121595501917 is a deficient number, since it is larger than the sum of its proper divisors (1).

121595501917 is an equidigital number, since it uses as much as digits as its factorization.

121595501917 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 141750, while the sum is 46.

The spelling of 121595501917 in words is "one hundred twenty-one billion, five hundred ninety-five million, five hundred one thousand, nine hundred seventeen".