155203123 has 4 divisors (see below), whose sum is σ = 159397840. Its totient is φ = 151008408.

The previous prime is 155203109. The next prime is 155203129. The reversal of 155203123 is 321302551.

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 155203123 - 2¹⁷ = 155072051 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 155203094 and 155203103.

It is not an unprimeable number, because it can be changed into a prime (155203129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2097303 + ... + 2097376.

It is an arithmetic number, because the mean of its divisors is an integer number (39849460).

Almost surely, 2^155203123 is an apocalyptic number.

155203123 is a deficient number, since it is larger than the sum of its proper divisors (4194717).

155203123 is an equidigital number, since it uses as much as digits as its factorization.

155203123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4194716.

The product of its (nonzero) digits is 900, while the sum is 22.

The square root of 155203123 is about 12458.0545431460. The cubic root of 155203123 is about 537.4030809928.

Adding to 155203123 its reverse (321302551), we get a palindrome (476505674).

The spelling of 155203123 in words is "one hundred fifty-five million, two hundred three thousand, one hundred twenty-three".