121968391 has 8 divisors (see below), whose sum is σ = 131858480. Its totient is φ = 112425408.

The previous prime is 121968373. The next prime is 121968397. The reversal of 121968391 is 193869121.

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 121968391 - 2⁷ = 121968263 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121968397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86046 + ... + 87451.

It is an arithmetic number, because the mean of its divisors is an integer number (16482310).

Almost surely, 2^121968391 is an apocalyptic number.

121968391 is a deficient number, since it is larger than the sum of its proper divisors (9890089).

121968391 is a wasteful number, since it uses less digits than its factorization.

121968391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173553.

The product of its digits is 23328, while the sum is 40.

The square root of 121968391 is about 11043.9300522957. The cubic root of 121968391 is about 495.9247292451.

The spelling of 121968391 in words is "one hundred twenty-one million, nine hundred sixty-eight thousand, three hundred ninety-one".