121728897 has 12 divisors (see below), whose sum is σ = 176716800. Its totient is φ = 80743608.

The previous prime is 121728881. The next prime is 121728899. The reversal of 121728897 is 798827121.

It is not a de Polignac number, because 121728897 - 2⁴ = 121728881 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121728899) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 32193 + ... + 35774.

It is an arithmetic number, because the mean of its divisors is an integer number (14726400).

Almost surely, 2^121728897 is an apocalyptic number.

It is an amenable number.

121728897 is a deficient number, since it is larger than the sum of its proper divisors (54987903).

121728897 is a wasteful number, since it uses less digits than its factorization.

121728897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68172 (or 68169 counting only the distinct ones).

The product of its digits is 112896, while the sum is 45.

The square root of 121728897 is about 11033.0819357059. The cubic root of 121728897 is about 495.5999215371.

The spelling of 121728897 in words is "one hundred twenty-one million, seven hundred twenty-eight thousand, eight hundred ninety-seven".