83156561 has 2 divisors, whose sum is σ = 83156562. Its totient is φ = 83156560.

The previous prime is 83156531. The next prime is 83156599. The reversal of 83156561 is 16565138.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 83156161 + 400 = 9119^2 + 20^2 .

It is a cyclic number.

It is not a de Polignac number, because 83156561 - 2⁶ = 83156497 is a prime.

It is not a weakly prime, because it can be changed into another prime (83156531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41578280 + 41578281.

It is an arithmetic number, because the mean of its divisors is an integer number (41578281).

Almost surely, 2^83156561 is an apocalyptic number.

It is an amenable number.

83156561 is a deficient number, since it is larger than the sum of its proper divisors (1).

83156561 is an equidigital number, since it uses as much as digits as its factorization.

83156561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21600, while the sum is 35.

The square root of 83156561 is about 9119.0219322030. The cubic root of 83156561 is about 436.4811640119.

The spelling of 83156561 in words is "eighty-three million, one hundred fifty-six thousand, five hundred sixty-one".