121155231121 has 4 divisors (see below), whose sum is σ = 123441178932. Its totient is φ = 118869283312.

The previous prime is 121155231103. The next prime is 121155231137. The reversal of 121155231121 is 121132551121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 121132551121 = 37 ⋅3273852733.

It can be written as a sum of positive squares in 2 ways, for example, as 77542756225 + 43612474896 = 278465^2 + 208836^2 .

It is a cyclic number.

It is not a de Polignac number, because 121155231121 - 2¹¹ = 121155229073 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121155271121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1142973826 + ... + 1142973931.

It is an arithmetic number, because the mean of its divisors is an integer number (30860294733).

Almost surely, 2^121155231121 is an apocalyptic number.

It is an amenable number.

121155231121 is a deficient number, since it is larger than the sum of its proper divisors (2285947811).

121155231121 is an equidigital number, since it uses as much as digits as its factorization.

121155231121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2285947810.

The product of its digits is 600, while the sum is 25.

Adding to 121155231121 its reverse (121132551121), we get a palindrome (242287782242).

The spelling of 121155231121 in words is "one hundred twenty-one billion, one hundred fifty-five million, two hundred thirty-one thousand, one hundred twenty-one".