2128685845387 has 4 divisors (see below), whose sum is σ = 2133624792096. Its totient is φ = 2123746898680.

The previous prime is 2128685845367. The next prime is 2128685845393. The reversal of 2128685845387 is 7835485868212.

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-2128685845387 is a prime.

It is a Smith number, since the sum of its digits (67) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2128685845367) 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, 2469472708 + ... + 2469473569.

It is an arithmetic number, because the mean of its divisors is an integer number (533406198024).

Almost surely, 2^{2128685845387} is an apocalyptic number.

2128685845387 is a deficient number, since it is larger than the sum of its proper divisors (4938946709).

2128685845387 is an equidigital number, since it uses as much as digits as its factorization.

2128685845387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4938946708.

The product of its digits is 206438400, while the sum is 67.

The spelling of 2128685845387 in words is "two trillion, one hundred twenty-eight billion, six hundred eighty-five million, eight hundred forty-five thousand, three hundred eighty-seven".