121601728 has 28 divisors (see below), whose sum is σ = 241904520. Its totient is φ = 60649472.

The previous prime is 121601707. The next prime is 121601741. The reversal of 121601728 is 827106121.

It is a junction number, because it is equal to n+sod(n) for n = 121601696 and 121601705.

It is an unprimeable number.

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, 26208 + ... + 30496.

Almost surely, 2^121601728 is an apocalyptic number.

It is an amenable number.

121601728 is a deficient number, since it is larger than the sum of its proper divisors (120302792).

121601728 is an equidigital number, since it uses as much as digits as its factorization.

121601728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4744 (or 4734 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 28.

The square root of 121601728 is about 11027.3173528288. The cubic root of 121601728 is about 495.4272785906.

Adding to 121601728 its reverse (827106121), we get a palindrome (948707849).

The spelling of 121601728 in words is "one hundred twenty-one million, six hundred one thousand, seven hundred twenty-eight".