156943561 has 2 divisors, whose sum is σ = 156943562. Its totient is φ = 156943560.

The previous prime is 156943543. The next prime is 156943601. The reversal of 156943561 is 165349651.

It is a happy number.

It is an a-pointer prime, because the next prime (156943601) can be obtained adding 156943561 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 150209536 + 6734025 = 12256^2 + 2595^2 .

It is a cyclic number.

It is not a de Polignac number, because 156943561 - 2⁷ = 156943433 is a prime.

It is not a weakly prime, because it can be changed into another prime (156943261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78471780 + 78471781.

It is an arithmetic number, because the mean of its divisors is an integer number (78471781).

Almost surely, 2^156943561 is an apocalyptic number.

It is an amenable number.

156943561 is a deficient number, since it is larger than the sum of its proper divisors (1).

156943561 is an equidigital number, since it uses as much as digits as its factorization.

156943561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 97200, while the sum is 40.

The square root of 156943561 is about 12527.7117224176. The cubic root of 156943561 is about 539.4044199497.

The spelling of 156943561 in words is "one hundred fifty-six million, nine hundred forty-three thousand, five hundred sixty-one".