121165155 has 48 divisors (see below), whose sum is σ = 216530496. Its totient is φ = 62649600.

The previous prime is 121165153. The next prime is 121165157. The reversal of 121165155 is 551561121.

121165155 is a `hidden beast` number, since 1 + 2 + 1 + 1 + 651 + 5 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (121165153) and next prime (121165157).

It is not a de Polignac number, because 121165155 - 2¹ = 121165153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121165151) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 240634 + ... + 241136.

It is an arithmetic number, because the mean of its divisors is an integer number (4511052).

Almost surely, 2^121165155 is an apocalyptic number.

121165155 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

121165155 is a deficient number, since it is larger than the sum of its proper divisors (95365341).

121165155 is a wasteful number, since it uses less digits than its factorization.

121165155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 668 (or 665 counting only the distinct ones).

The product of its digits is 1500, while the sum is 27.

The square root of 121165155 is about 11007.5044855771. The cubic root of 121165155 is about 494.8336753715.

It can be divided in two parts, 12116 and 5155, that added together give a palindrome (17271).

The spelling of 121165155 in words is "one hundred twenty-one million, one hundred sixty-five thousand, one hundred fifty-five".