123742555 has 4 divisors (see below), whose sum is σ = 148491072. Its totient is φ = 98994040.

The previous prime is 123742547. The next prime is 123742559. The reversal of 123742555 is 555247321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 555247321 = 1327 ⋅418423.

It is not a de Polignac number, because 123742555 - 2³ = 123742547 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 123742555.

It is not an unprimeable number, because it can be changed into a prime (123742559) 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, 12374251 + ... + 12374260.

It is an arithmetic number, because the mean of its divisors is an integer number (37122768).

Almost surely, 2^123742555 is an apocalyptic number.

123742555 is a deficient number, since it is larger than the sum of its proper divisors (24748517).

123742555 is an equidigital number, since it uses as much as digits as its factorization.

123742555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24748516.

The product of its digits is 42000, while the sum is 34.

The square root of 123742555 is about 11123.9630977453. The cubic root of 123742555 is about 498.3177531050.

Adding to 123742555 its reverse (555247321), we get a palindrome (678989876).

The spelling of 123742555 in words is "one hundred twenty-three million, seven hundred forty-two thousand, five hundred fifty-five".