128617551 has 10 divisors (see below), whose sum is σ = 192132512. Its totient is φ = 85744980.

The previous prime is 128617537. The next prime is 128617553. The reversal of 128617551 is 155716821.

128617551 is a `hidden beast` number, since 12 + 86 + 17 + 551 = 666.

It is not a de Polignac number, because 128617551 - 2¹⁵ = 128584783 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128617553) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 793855 + ... + 794016.

Almost surely, 2^128617551 is an apocalyptic number.

128617551 is a deficient number, since it is larger than the sum of its proper divisors (63514961).

128617551 is an equidigital number, since it uses as much as digits as its factorization.

128617551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1587883 (or 1587874 counting only the distinct ones).

The product of its digits is 16800, while the sum is 36.

The square root of 128617551 is about 11340.9678158436. The cubic root of 128617551 is about 504.7776049142. Note that the first 3 decimals are identical.

The spelling of 128617551 in words is "one hundred twenty-eight million, six hundred seventeen thousand, five hundred fifty-one".