2128187771257 has 4 divisors (see below), whose sum is σ = 2128415564800. Its totient is φ = 2127959977716.

The previous prime is 2128187771239. The next prime is 2128187771263. The reversal of 2128187771257 is 7521777818212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2128187771257 - 2¹⁵ = 2128187738489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2128187771267) 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, 113882757 + ... + 113901442.

It is an arithmetic number, because the mean of its divisors is an integer number (532103891200).

Almost surely, 2^{2128187771257} is an apocalyptic number.

It is an amenable number.

2128187771257 is a deficient number, since it is larger than the sum of its proper divisors (227793543).

2128187771257 is an equidigital number, since it uses as much as digits as its factorization.

2128187771257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227793542.

The product of its digits is 6146560, while the sum is 58.

The spelling of 2128187771257 in words is "two trillion, one hundred twenty-eight billion, one hundred eighty-seven million, seven hundred seventy-one thousand, two hundred fifty-seven".