121553143 has 4 divisors (see below), whose sum is σ = 121637248. Its totient is φ = 121469040.

The previous prime is 121553041. The next prime is 121553149. The reversal of 121553143 is 341355121.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121553143 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121553149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39846 + ... + 42787.

It is an arithmetic number, because the mean of its divisors is an integer number (30409312).

Almost surely, 2^121553143 is an apocalyptic number.

121553143 is a deficient number, since it is larger than the sum of its proper divisors (84105).

121553143 is an equidigital number, since it uses as much as digits as its factorization.

121553143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84104.

The product of its digits is 1800, while the sum is 25.

The square root of 121553143 is about 11025.1141944199. The cubic root of 121553143 is about 495.3612884627.

The spelling of 121553143 in words is "one hundred twenty-one million, five hundred fifty-three thousand, one hundred forty-three".