156856009 has 2 divisors, whose sum is σ = 156856010. Its totient is φ = 156856008.

The previous prime is 156855947. The next prime is 156856019. The reversal of 156856009 is 900658651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 149817600 + 7038409 = 12240^2 + 2653^2 .

It is a cyclic number.

It is not a de Polignac number, because 156856009 - 2¹⁵ = 156823241 is a prime.

It is not a weakly prime, because it can be changed into another prime (156856019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78428004 + 78428005.

It is an arithmetic number, because the mean of its divisors is an integer number (78428005).

Almost surely, 2^156856009 is an apocalyptic number.

It is an amenable number.

156856009 is a deficient number, since it is larger than the sum of its proper divisors (1).

156856009 is an equidigital number, since it uses as much as digits as its factorization.

156856009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64800, while the sum is 40.

The square root of 156856009 is about 12524.2169016669. The cubic root of 156856009 is about 539.3040978552.

The spelling of 156856009 in words is "one hundred fifty-six million, eight hundred fifty-six thousand, nine".