121565065819 has 2 divisors, whose sum is σ = 121565065820. Its totient is φ = 121565065818.

The previous prime is 121565065781. The next prime is 121565065829. The reversal of 121565065819 is 918560565121.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121565065819 is a prime.

It is a super-2 number, since 2×121565065819² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (121565065829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60782532909 + 60782532910.

It is an arithmetic number, because the mean of its divisors is an integer number (60782532910).

Almost surely, 2^121565065819 is an apocalyptic number.

121565065819 is a deficient number, since it is larger than the sum of its proper divisors (1).

121565065819 is an equidigital number, since it uses as much as digits as its factorization.

121565065819 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648000, while the sum is 49.

The spelling of 121565065819 in words is "one hundred twenty-one billion, five hundred sixty-five million, sixty-five thousand, eight hundred nineteen".