121691087571 has 8 divisors (see below), whose sum is σ = 167849776080. Its totient is φ = 78329895392.

The previous prime is 121691087561. The next prime is 121691087591. The reversal of 121691087571 is 175780196121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 121691087571 - 2⁷ = 121691087443 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 121691087571.

It is not an unprimeable number, because it can be changed into a prime (121691087561) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 699373980 + ... + 699374153.

It is an arithmetic number, because the mean of its divisors is an integer number (20981222010).

Almost surely, 2^121691087571 is an apocalyptic number.

121691087571 is a deficient number, since it is larger than the sum of its proper divisors (46158688509).

121691087571 is a wasteful number, since it uses less digits than its factorization.

121691087571 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1398748165.

The product of its (nonzero) digits is 211680, while the sum is 48.

The spelling of 121691087571 in words is "one hundred twenty-one billion, six hundred ninety-one million, eighty-seven thousand, five hundred seventy-one".