136640866 has 16 divisors (see below), whose sum is σ = 224502840. Its totient is φ = 62083840.

The previous prime is 136640851. The next prime is 136640869. The reversal of 136640866 is 668046631.

It can be written as a sum of positive squares in 4 ways, for example, as 136305625 + 335241 = 11675^2 + 579^2 .

It is a super-2 number, since 2×136640866² = 37341452522459912, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (136640869) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68305 + ... + 70276.

Almost surely, 2^136640866 is an apocalyptic number.

136640866 is a deficient number, since it is larger than the sum of its proper divisors (87861974).

136640866 is a wasteful number, since it uses less digits than its factorization.

136640866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138629.

The product of its (nonzero) digits is 124416, while the sum is 40.

The square root of 136640866 is about 11689.3483992907. The cubic root of 136640866 is about 515.0628207528.

The spelling of 136640866 in words is "one hundred thirty-six million, six hundred forty thousand, eight hundred sixty-six".