128668131 has 6 divisors (see below), whose sum is σ = 185853980. Its totient is φ = 85778748.

The previous prime is 128668123. The next prime is 128668139. The reversal of 128668131 is 131866821.

It is an interprime number because it is at equal distance from previous prime (128668123) and next prime (128668139).

It is not a de Polignac number, because 128668131 - 2³ = 128668123 is a prime.

It is a super-2 number, since 2×128668131² = 33110975870066322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128668139) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7148221 + ... + 7148238.

Almost surely, 2^128668131 is an apocalyptic number.

128668131 is a deficient number, since it is larger than the sum of its proper divisors (57185849).

128668131 is a wasteful number, since it uses less digits than its factorization.

128668131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14296465 (or 14296462 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 128668131 is about 11343.1975650607. The cubic root of 128668131 is about 504.8437656752.

The spelling of 128668131 in words is "one hundred twenty-eight million, six hundred sixty-eight thousand, one hundred thirty-one".