156840656081 has 4 divisors (see below), whose sum is σ = 157398808164. Its totient is φ = 156282504000.

The previous prime is 156840656053. The next prime is 156840656111. The reversal of 156840656081 is 180656048651.

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

It can be written as a sum of positive squares in 2 ways, for example, as 62028393025 + 94812263056 = 249055^2 + 307916^2 .

It is a cyclic number.

It is not a de Polignac number, because 156840656081 - 2¹⁰ = 156840655057 is a prime.

It is a super-2 number, since 2×156840656081² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (156840656041) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 279075620 + ... + 279076181.

It is an arithmetic number, because the mean of its divisors is an integer number (39349702041).

Almost surely, 2^156840656081 is an apocalyptic number.

It is an amenable number.

156840656081 is a deficient number, since it is larger than the sum of its proper divisors (558152083).

156840656081 is an equidigital number, since it uses as much as digits as its factorization.

156840656081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 558152082.

The product of its (nonzero) digits is 1382400, while the sum is 50.

The spelling of 156840656081 in words is "one hundred fifty-six billion, eight hundred forty million, six hundred fifty-six thousand, eighty-one".