121017905819 has 2 divisors, whose sum is σ = 121017905820. Its totient is φ = 121017905818.

The previous prime is 121017905783. The next prime is 121017905849. The reversal of 121017905819 is 918509710121.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 121017905819 - 2⁸ = 121017905563 is a prime.

It is a super-2 number, since 2×121017905819² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 121017905819.

It is not a weakly prime, because it can be changed into another prime (121017905849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60508952909 + 60508952910.

It is an arithmetic number, because the mean of its divisors is an integer number (60508952910).

Almost surely, 2^121017905819 is an apocalyptic number.

121017905819 is a deficient number, since it is larger than the sum of its proper divisors (1).

121017905819 is an equidigital number, since it uses as much as digits as its factorization.

121017905819 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 45360, while the sum is 44.

The spelling of 121017905819 in words is "one hundred twenty-one billion, seventeen million, nine hundred five thousand, eight hundred nineteen".