121712155 has 8 divisors (see below), whose sum is σ = 146317392. Its totient is φ = 97194528.

The previous prime is 121712137. The next prime is 121712167. The reversal of 121712155 is 551217121.

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 121712155 - 2⁹ = 121711643 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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, 18804 + ... + 24433.

It is an arithmetic number, because the mean of its divisors is an integer number (18289674).

Almost surely, 2^121712155 is an apocalyptic number.

121712155 is a deficient number, since it is larger than the sum of its proper divisors (24605237).

121712155 is an equidigital number, since it uses as much as digits as its factorization.

121712155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43805.

The product of its digits is 700, while the sum is 25.

The square root of 121712155 is about 11032.3231914226. The cubic root of 121712155 is about 495.5771996951.

Adding to 121712155 its reverse (551217121), we get a palindrome (672929276).

The spelling of 121712155 in words is "one hundred twenty-one million, seven hundred twelve thousand, one hundred fifty-five".