135665123 has 4 divisors (see below), whose sum is σ = 147998328. Its totient is φ = 123331920.

The previous prime is 135665099. The next prime is 135665137. The reversal of 135665123 is 321566531.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 135665123 - 2¹⁰ = 135664099 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 135665123.

It is not an unprimeable number, because it can be changed into a prime (135665143) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6166586 + ... + 6166607.

It is an arithmetic number, because the mean of its divisors is an integer number (36999582).

Almost surely, 2^135665123 is an apocalyptic number.

135665123 is a deficient number, since it is larger than the sum of its proper divisors (12333205).

135665123 is a wasteful number, since it uses less digits than its factorization.

135665123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12333204.

The product of its digits is 16200, while the sum is 32.

The square root of 135665123 is about 11647.5372074958. The cubic root of 135665123 is about 513.8338814776.

The spelling of 135665123 in words is "one hundred thirty-five million, six hundred sixty-five thousand, one hundred twenty-three".