156641543909 has 2 divisors, whose sum is σ = 156641543910. Its totient is φ = 156641543908.

The previous prime is 156641543857. The next prime is 156641543969. The reversal of 156641543909 is 909345146651.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 135955913284 + 20685630625 = 368722^2 + 143825^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-156641543909 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (156641543969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78320771954 + 78320771955.

It is an arithmetic number, because the mean of its divisors is an integer number (78320771955).

Almost surely, 2^156641543909 is an apocalyptic number.

It is an amenable number.

156641543909 is a deficient number, since it is larger than the sum of its proper divisors (1).

156641543909 is an equidigital number, since it uses as much as digits as its factorization.

156641543909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3499200, while the sum is 53.

The spelling of 156641543909 in words is "one hundred fifty-six billion, six hundred forty-one million, five hundred forty-three thousand, nine hundred nine".