121575817 has 4 divisors (see below), whose sum is σ = 132628176. Its totient is φ = 110523460.

The previous prime is 121575803. The next prime is 121575847. The reversal of 121575817 is 718575121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 718575121 = 11 ⋅65325011.

It is a cyclic number.

It is not a de Polignac number, because 121575817 - 2¹⁹ = 121051529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121575847) 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, 5526163 + ... + 5526184.

It is an arithmetic number, because the mean of its divisors is an integer number (33157044).

Almost surely, 2^121575817 is an apocalyptic number.

It is an amenable number.

121575817 is a deficient number, since it is larger than the sum of its proper divisors (11052359).

121575817 is a wasteful number, since it uses less digits than its factorization.

121575817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11052358.

The product of its digits is 19600, while the sum is 37.

The square root of 121575817 is about 11026.1424351402. The cubic root of 121575817 is about 495.3920874019.

The spelling of 121575817 in words is "one hundred twenty-one million, five hundred seventy-five thousand, eight hundred seventeen".