156843683681 has 4 divisors (see below), whose sum is σ = 157516832772. Its totient is φ = 156170534592.

The previous prime is 156843683653. The next prime is 156843683687. The reversal of 156843683681 is 186386348651.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 186386348651 = 79 ⋅2359320869.

It can be written as a sum of positive squares in 2 ways, for example, as 95644840225 + 61198843456 = 309265^2 + 247384^2 .

It is a cyclic number.

It is not a de Polignac number, because 156843683681 - 2⁶ = 156843683617 is a prime.

It is a super-2 number, since 2×156843683681² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 156843683681.

It is not an unprimeable number, because it can be changed into a prime (156843683687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 336574196 + ... + 336574661.

It is an arithmetic number, because the mean of its divisors is an integer number (39379208193).

Almost surely, 2^156843683681 is an apocalyptic number.

It is an amenable number.

156843683681 is a deficient number, since it is larger than the sum of its proper divisors (673149091).

156843683681 is an equidigital number, since it uses as much as digits as its factorization.

156843683681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 673149090.

The product of its digits is 19906560, while the sum is 59.

The spelling of 156843683681 in words is "one hundred fifty-six billion, eight hundred forty-three million, six hundred eighty-three thousand, six hundred eighty-one".