121243142155 has 8 divisors (see below), whose sum is σ = 146904312672. Its totient is φ = 96052819008.

The previous prime is 121243142117. The next prime is 121243142161. The reversal of 121243142155 is 551241342121.

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 121243142155 - 2¹⁷ = 121243011083 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 (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 117711274 + ... + 117712303.

It is an arithmetic number, because the mean of its divisors is an integer number (18363039084).

Almost surely, 2^121243142155 is an apocalyptic number.

121243142155 is a deficient number, since it is larger than the sum of its proper divisors (25661170517).

121243142155 is a wasteful number, since it uses less digits than its factorization.

121243142155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 235423685.

The product of its digits is 9600, while the sum is 31.

Adding to 121243142155 its reverse (551241342121), we get a palindrome (672484484276).

The spelling of 121243142155 in words is "one hundred twenty-one billion, two hundred forty-three million, one hundred forty-two thousand, one hundred fifty-five".