42155123 has 4 divisors (see below), whose sum is σ = 42434448. Its totient is φ = 41875800.

The previous prime is 42155107. The next prime is 42155131. The reversal of 42155123 is 32155124.

42155123 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 42155123 - 2⁴ = 42155107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42157123) 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, 139436 + ... + 139737.

It is an arithmetic number, because the mean of its divisors is an integer number (10608612).

Almost surely, 2^42155123 is an apocalyptic number.

42155123 is a deficient number, since it is larger than the sum of its proper divisors (279325).

42155123 is a wasteful number, since it uses less digits than its factorization.

42155123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 279324.

The product of its digits is 1200, while the sum is 23.

The square root of 42155123 is about 6492.6976673799. The cubic root of 42155123 is about 348.0300844868.

Subtracting from 42155123 its reverse (32155124), we obtain a palindrome (9999999).

The spelling of 42155123 in words is "forty-two million, one hundred fifty-five thousand, one hundred twenty-three".