128003971 has 4 divisors (see below), whose sum is σ = 129246832. Its totient is φ = 126761112.

The previous prime is 128003959. The next prime is 128003977. The reversal of 128003971 is 179300821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 179300821 = 7 ⋅25614403.

It is a cyclic number.

It is not a de Polignac number, because 128003971 - 2⁹ = 128003459 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128003977) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 621276 + ... + 621481.

It is an arithmetic number, because the mean of its divisors is an integer number (32311708).

Almost surely, 2^128003971 is an apocalyptic number.

128003971 is a deficient number, since it is larger than the sum of its proper divisors (1242861).

128003971 is a wasteful number, since it uses less digits than its factorization.

128003971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1242860.

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 128003971 is about 11313.8839926879. The cubic root of 128003971 is about 503.9736315150.

The spelling of 128003971 in words is "one hundred twenty-eight million, three thousand, nine hundred seventy-one".