128405715 has 16 divisors (see below), whose sum is σ = 205610400. Its totient is φ = 68429312.

The previous prime is 128405713. The next prime is 128405737. The reversal of 128405715 is 517504821.

It is a cyclic number.

It is not a de Polignac number, because 128405715 - 2¹ = 128405713 is a prime.

It is a super-4 number, since 4×128405715⁴ (a number of 34 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (128405713) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23131 + ... + 28139.

It is an arithmetic number, because the mean of its divisors is an integer number (12850650).

Almost surely, 2^128405715 is an apocalyptic number.

128405715 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

128405715 is a deficient number, since it is larger than the sum of its proper divisors (77204685).

128405715 is a wasteful number, since it uses less digits than its factorization.

128405715 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6726.

The product of its (nonzero) digits is 11200, while the sum is 33.

The square root of 128405715 is about 11331.6245525520. The cubic root of 128405715 is about 504.5003259398.

The spelling of 128405715 in words is "one hundred twenty-eight million, four hundred five thousand, seven hundred fifteen".