128007649 has 48 divisors (see below), whose sum is σ = 172302336. Its totient is φ = 93895200.

The previous prime is 128007619. The next prime is 128007661. The reversal of 128007649 is 946700821.

It is not a de Polignac number, because 128007649 - 2¹¹ = 128005601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128007619) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 785242 + ... + 785404.

It is an arithmetic number, because the mean of its divisors is an integer number (3589632).

Almost surely, 2^128007649 is an apocalyptic number.

It is an amenable number.

128007649 is a deficient number, since it is larger than the sum of its proper divisors (44294687).

128007649 is a wasteful number, since it uses less digits than its factorization.

128007649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266 (or 259 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 128007649 is about 11314.0465351703. The cubic root of 128007649 is about 503.9784584414.

It can be divided in two parts, 12800 and 7649, that added together give a square (20449 = 143²).

The spelling of 128007649 in words is "one hundred twenty-eight million, seven thousand, six hundred forty-nine".