121555113 has 16 divisors (see below), whose sum is σ = 165881856. Its totient is φ = 79140240.

The previous prime is 121555111. The next prime is 121555121. The reversal of 121555113 is 311555121.

It is not a de Polignac number, because 121555113 - 2¹ = 121555111 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121555111) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 113820 + ... + 114882.

It is an arithmetic number, because the mean of its divisors is an integer number (10367616).

Almost surely, 2^121555113 is an apocalyptic number.

It is an amenable number.

121555113 is a deficient number, since it is larger than the sum of its proper divisors (44326743).

121555113 is a wasteful number, since it uses less digits than its factorization.

121555113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1924.

The product of its digits is 750, while the sum is 24.

The square root of 121555113 is about 11025.2035355362. The cubic root of 121555113 is about 495.3639645391.

The spelling of 121555113 in words is "one hundred twenty-one million, five hundred fifty-five thousand, one hundred thirteen".