121288939 has 4 divisors (see below), whose sum is σ = 124109656. Its totient is φ = 118468224.

The previous prime is 121288907. The next prime is 121288943. The reversal of 121288939 is 939882121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 121288939 - 2⁵ = 121288907 is a prime.

It is a super-2 number, since 2×121288939² = 29422013447491442, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (43), and also a Moran number because the ratio is a prime number: 2820673 = 121288939 / (1 + 2 + 1 + 2 + 8 + 8 + 9 + 3 + 9).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121288895 and 121288904.

It is not an unprimeable number, because it can be changed into a prime (121288949) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1410294 + ... + 1410379.

It is an arithmetic number, because the mean of its divisors is an integer number (31027414).

Almost surely, 2^121288939 is an apocalyptic number.

121288939 is a deficient number, since it is larger than the sum of its proper divisors (2820717).

121288939 is an equidigital number, since it uses as much as digits as its factorization.

121288939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2820716.

The product of its digits is 62208, while the sum is 43.

The square root of 121288939 is about 11013.1257597469. The cubic root of 121288939 is about 495.0021276649.

The spelling of 121288939 in words is "one hundred twenty-one million, two hundred eighty-eight thousand, nine hundred thirty-nine".