156442819493 has 4 divisors (see below), whose sum is σ = 157125976140. Its totient is φ = 155759662848.

The previous prime is 156442819487. The next prime is 156442819513. The reversal of 156442819493 is 394918244651.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 394918244651 = 7 ⋅56416892093.

It can be written as a sum of positive squares in 2 ways, for example, as 108508971649 + 47933847844 = 329407^2 + 218938^2 .

It is a cyclic number.

It is not a de Polignac number, because 156442819493 - 2⁸ = 156442819237 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 (156442819693) 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, 341577980 + ... + 341578437.

It is an arithmetic number, because the mean of its divisors is an integer number (39281494035).

Almost surely, 2^156442819493 is an apocalyptic number.

It is an amenable number.

156442819493 is a deficient number, since it is larger than the sum of its proper divisors (683156647).

156442819493 is an equidigital number, since it uses as much as digits as its factorization.

156442819493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 683156646.

The product of its digits is 7464960, while the sum is 56.

The spelling of 156442819493 in words is "one hundred fifty-six billion, four hundred forty-two million, eight hundred nineteen thousand, four hundred ninety-three".