136640023 has 4 divisors (see below), whose sum is σ = 147150808. Its totient is φ = 126129240.

The previous prime is 136640017. The next prime is 136640057. The reversal of 136640023 is 320046631.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 320046631 = 277 ⋅1155403.

It is a cyclic number.

It is not a de Polignac number, because 136640023 - 2⁵ = 136639991 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 136640023.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (136640323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5255373 + ... + 5255398.

It is an arithmetic number, because the mean of its divisors is an integer number (36787702).

Almost surely, 2^136640023 is an apocalyptic number.

136640023 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

136640023 is a deficient number, since it is larger than the sum of its proper divisors (10510785).

136640023 is a wasteful number, since it uses less digits than its factorization.

136640023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10510784.

The product of its (nonzero) digits is 2592, while the sum is 25.

The square root of 136640023 is about 11689.3123407667. The cubic root of 136640023 is about 515.0617615313.

Adding to 136640023 its reverse (320046631), we get a palindrome (456686654).

The spelling of 136640023 in words is "one hundred thirty-six million, six hundred forty thousand, twenty-three".