136866561 has 16 divisors (see below), whose sum is σ = 196761600. Its totient is φ = 84124800.

The previous prime is 136866559. The next prime is 136866571. The reversal of 136866561 is 165668631.

It is not a de Polignac number, because 136866561 - 2¹ = 136866559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (136866571) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43365 + ... + 46413.

It is an arithmetic number, because the mean of its divisors is an integer number (12297600).

Almost surely, 2^136866561 is an apocalyptic number.

It is an amenable number.

136866561 is a deficient number, since it is larger than the sum of its proper divisors (59895039).

136866561 is a wasteful number, since it uses less digits than its factorization.

136866561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4216.

The product of its digits is 155520, while the sum is 42.

The square root of 136866561 is about 11698.9982904521. The cubic root of 136866561 is about 515.3462478175.

The spelling of 136866561 in words is "one hundred thirty-six million, eight hundred sixty-six thousand, five hundred sixty-one".