121685884567509 has 16 divisors (see below), whose sum is σ = 162321627483072. Its totient is φ = 81087033675648.

The previous prime is 121685884567459. The next prime is 121685884567547. The reversal of 121685884567509 is 905765488586121.

It is not a de Polignac number, because 121685884567509 - 2²¹ = 121685882470357 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121685884566509) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 464359729 + ... + 464621705.

It is an arithmetic number, because the mean of its divisors is an integer number (10145101717692).

Almost surely, 2^{121685884567509} is an apocalyptic number.

It is an amenable number.

121685884567509 is a deficient number, since it is larger than the sum of its proper divisors (40635742915563).

121685884567509 is a wasteful number, since it uses less digits than its factorization.

121685884567509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331796.

The product of its (nonzero) digits is 1161216000, while the sum is 75.

The spelling of 121685884567509 in words is "one hundred twenty-one trillion, six hundred eighty-five billion, eight hundred eighty-four million, five hundred sixty-seven thousand, five hundred nine".