128540723719 has 4 divisors (see below), whose sum is σ = 130647948760. Its totient is φ = 126433498680.

The previous prime is 128540723713. The next prime is 128540723747. The reversal of 128540723719 is 917327045821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 917327045821 = 43609 ⋅21035269.

It is a cyclic number.

It is not a de Polignac number, because 128540723719 - 2¹⁷ = 128540592647 is a prime.

It is a super-2 number, since 2×128540723719² (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 (128540723713) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1053612429 + ... + 1053612550.

It is an arithmetic number, because the mean of its divisors is an integer number (32661987190).

Almost surely, 2^128540723719 is an apocalyptic number.

128540723719 is a deficient number, since it is larger than the sum of its proper divisors (2107225041).

128540723719 is an equidigital number, since it uses as much as digits as its factorization.

128540723719 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2107225040.

The product of its (nonzero) digits is 846720, while the sum is 49.

The spelling of 128540723719 in words is "one hundred twenty-eight billion, five hundred forty million, seven hundred twenty-three thousand, seven hundred nineteen".