121705517645 has 16 divisors (see below), whose sum is σ = 146243784960. Its totient is φ = 97233057600.

The previous prime is 121705517587. The next prime is 121705517657. The reversal of 121705517645 is 546715507121.

It is not a de Polignac number, because 121705517645 - 2⁸ = 121705517389 is a prime.

It is a super-3 number, since 3×121705517645³ (a number of 34 digits) contains 333 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 121705517596 and 121705517605.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20840636 + ... + 20846474.

It is an arithmetic number, because the mean of its divisors is an integer number (9140236560).

Almost surely, 2^121705517645 is an apocalyptic number.

It is an amenable number.

121705517645 is a deficient number, since it is larger than the sum of its proper divisors (24538267315).

121705517645 is a wasteful number, since it uses less digits than its factorization.

121705517645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10756.

The product of its (nonzero) digits is 294000, while the sum is 44.

The spelling of 121705517645 in words is "one hundred twenty-one billion, seven hundred five million, five hundred seventeen thousand, six hundred forty-five".