121553155 has 8 divisors (see below), whose sum is σ = 146046384. Its totient is φ = 97120800.

The previous prime is 121553149. The next prime is 121553161. The reversal of 121553155 is 551355121.

It is an interprime number because it is at equal distance from previous prime (121553149) and next prime (121553161).

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

It is a de Polignac number, because none of the positive numbers 2^k-121553155 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, 10701 + ... + 18910.

It is an arithmetic number, because the mean of its divisors is an integer number (18255798).

Almost surely, 2^121553155 is an apocalyptic number.

121553155 is a deficient number, since it is larger than the sum of its proper divisors (24493229).

121553155 is an equidigital number, since it uses as much as digits as its factorization.

121553155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30437.

The product of its digits is 3750, while the sum is 28.

The square root of 121553155 is about 11025.1147386320. The cubic root of 121553155 is about 495.3613047638.

The spelling of 121553155 in words is "one hundred twenty-one million, five hundred fifty-three thousand, one hundred fifty-five".