156728005778 has 4 divisors (see below), whose sum is σ = 235092008670. Its totient is φ = 78364002888.

The previous prime is 156728005717. The next prime is 156728005799. The reversal of 156728005778 is 877500827651.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 153089865289 + 3638140489 = 391267^2 + 60317^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39182001443 + ... + 39182001446.

Almost surely, 2^156728005778 is an apocalyptic number.

156728005778 is a deficient number, since it is larger than the sum of its proper divisors (78364002892).

156728005778 is an equidigital number, since it uses as much as digits as its factorization.

156728005778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78364002891.

The product of its (nonzero) digits is 6585600, while the sum is 56.

The spelling of 156728005778 in words is "one hundred fifty-six billion, seven hundred twenty-eight million, five thousand, seven hundred seventy-eight".