128663253115551 has 24 divisors (see below), whose sum is σ = 231705252365184. Its totient is φ = 66838053566160.

The previous prime is 128663253115549. The next prime is 128663253115577. The reversal of 128663253115551 is 155511352366821.

128663253115551 is a `hidden beast` number, since 1 + 2 + 8 + 6 + 6 + 3 + 2 + 531 + 1 + 55 + 51 = 666.

It is not a de Polignac number, because 128663253115551 - 2¹ = 128663253115549 is a prime.

It is a super-4 number, since 4×128663253115551⁴ (a number of 58 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128663253111551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 92830629261 + ... + 92830630646.

It is an arithmetic number, because the mean of its divisors is an integer number (9654385515216).

Almost surely, 2^{128663253115551} is an apocalyptic number.

128663253115551 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

128663253115551 is a deficient number, since it is larger than the sum of its proper divisors (103041999249633).

128663253115551 is a wasteful number, since it uses less digits than its factorization.

128663253115551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185661259931 (or 185661259928 counting only the distinct ones).

The product of its digits is 6480000, while the sum is 54.

The spelling of 128663253115551 in words is "one hundred twenty-eight trillion, six hundred sixty-three billion, two hundred fifty-three million, one hundred fifteen thousand, five hundred fifty-one".