128316777643 has 4 divisors (see below), whose sum is σ = 128329051968. Its totient is φ = 128304503320.

The previous prime is 128316777619. The next prime is 128316777661. The reversal of 128316777643 is 346777613821.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128316777643 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128316777943) 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, 6121468 + ... + 6142393.

It is an arithmetic number, because the mean of its divisors is an integer number (32082262992).

Almost surely, 2^128316777643 is an apocalyptic number.

128316777643 is a deficient number, since it is larger than the sum of its proper divisors (12274325).

128316777643 is a wasteful number, since it uses less digits than its factorization.

128316777643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12274324.

The product of its digits is 7112448, while the sum is 55.

The spelling of 128316777643 in words is "one hundred twenty-eight billion, three hundred sixteen million, seven hundred seventy-seven thousand, six hundred forty-three".