121531161 has 8 divisors (see below), whose sum is σ = 163476000. Its totient is φ = 80303552.

The previous prime is 121531159. The next prime is 121531171. The reversal of 121531161 is 161135121.

It is a happy number.

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 121531161 - 2¹ = 121531159 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121531171) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 178911 + ... + 179588.

It is an arithmetic number, because the mean of its divisors is an integer number (20434500).

Almost surely, 2^121531161 is an apocalyptic number.

It is an amenable number.

121531161 is a deficient number, since it is larger than the sum of its proper divisors (41944839).

121531161 is a wasteful number, since it uses less digits than its factorization.

121531161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 358615.

The product of its digits is 180, while the sum is 21.

The square root of 121531161 is about 11024.1172435710. The cubic root of 121531161 is about 495.3314258363.

Adding to 121531161 its reverse (161135121), we get a palindrome (282666282).

The spelling of 121531161 in words is "one hundred twenty-one million, five hundred thirty-one thousand, one hundred sixty-one".