158816561 has 2 divisors, whose sum is σ = 158816562. Its totient is φ = 158816560.

The previous prime is 158816551. The next prime is 158816579. The reversal of 158816561 is 165618851.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 157753600 + 1062961 = 12560^2 + 1031^2 .

It is a cyclic number.

It is not a de Polignac number, because 158816561 - 2¹⁰ = 158815537 is a prime.

It is not a weakly prime, because it can be changed into another prime (158816521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 79408280 + 79408281.

It is an arithmetic number, because the mean of its divisors is an integer number (79408281).

Almost surely, 2^158816561 is an apocalyptic number.

It is an amenable number.

158816561 is a deficient number, since it is larger than the sum of its proper divisors (1).

158816561 is an equidigital number, since it uses as much as digits as its factorization.

158816561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 57600, while the sum is 41.

The square root of 158816561 is about 12602.2442842535. The cubic root of 158816561 is about 541.5417314805.

The spelling of 158816561 in words is "one hundred fifty-eight million, eight hundred sixteen thousand, five hundred sixty-one".