128263813 has 4 divisors (see below), whose sum is σ = 135014560. Its totient is φ = 121513068.

The previous prime is 128263783. The next prime is 128263859. The reversal of 128263813 is 318362821.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 318362821 = 7 ⋅45480403.

It is a cyclic number.

It is not a de Polignac number, because 128263813 - 2⁹ = 128263301 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128263873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3375345 + ... + 3375382.

It is an arithmetic number, because the mean of its divisors is an integer number (33753640).

Almost surely, 2^128263813 is an apocalyptic number.

It is an amenable number.

128263813 is a deficient number, since it is larger than the sum of its proper divisors (6750747).

128263813 is an equidigital number, since it uses as much as digits as its factorization.

128263813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6750746.

The product of its digits is 13824, while the sum is 34.

The square root of 128263813 is about 11325.3614953343. The cubic root of 128263813 is about 504.3144152301.

The spelling of 128263813 in words is "one hundred twenty-eight million, two hundred sixty-three thousand, eight hundred thirteen".