128893776493 has 4 divisors (see below), whose sum is σ = 128894822460. Its totient is φ = 128892730528.

The previous prime is 128893776437. The next prime is 128893776523. The reversal of 128893776493 is 394677398821.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 394677398821 = 317 ⋅1245039113.

It can be written as a sum of positive squares in 2 ways, for example, as 65207197449 + 63686579044 = 255357^2 + 252362^2 .

It is a cyclic number.

It is not a de Polignac number, because 128893776493 - 2¹³ = 128893768301 is a prime.

It is a super-2 number, since 2×128893776493² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128893776293) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 308938 + ... + 594331.

It is an arithmetic number, because the mean of its divisors is an integer number (32223705615).

Almost surely, 2^128893776493 is an apocalyptic number.

It is an amenable number.

128893776493 is a deficient number, since it is larger than the sum of its proper divisors (1045967).

128893776493 is an equidigital number, since it uses as much as digits as its factorization.

128893776493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1045966.

The product of its digits is 109734912, while the sum is 67.

The spelling of 128893776493 in words is "one hundred twenty-eight billion, eight hundred ninety-three million, seven hundred seventy-six thousand, four hundred ninety-three".