128720733 has 16 divisors (see below), whose sum is σ = 175654656. Its totient is φ = 83808320.

The previous prime is 128720701. The next prime is 128720741. The reversal of 128720733 is 337027821.

It is a cyclic number.

It is not a de Polignac number, because 128720733 - 2⁵ = 128720701 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 128720694 and 128720703.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128720833) 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 15 ways as a sum of consecutive naturals, for example, 108403 + ... + 109583.

It is an arithmetic number, because the mean of its divisors is an integer number (10978416).

Almost surely, 2^128720733 is an apocalyptic number.

It is an amenable number.

128720733 is a deficient number, since it is larger than the sum of its proper divisors (46933923).

128720733 is a wasteful number, since it uses less digits than its factorization.

128720733 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2004.

The product of its (nonzero) digits is 14112, while the sum is 33.

The square root of 128720733 is about 11345.5159865032. The cubic root of 128720733 is about 504.9125529072.

The spelling of 128720733 in words is "one hundred twenty-eight million, seven hundred twenty thousand, seven hundred thirty-three".