42123505 has 4 divisors (see below), whose sum is σ = 50548212. Its totient is φ = 33698800.

The previous prime is 42123493. The next prime is 42123509. The reversal of 42123505 is 50532124.

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

It can be written as a sum of positive squares in 2 ways, for example, as 14371681 + 27751824 = 3791^2 + 5268^2 .

It is not a de Polignac number, because 42123505 - 2¹³ = 42115313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42123509) 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, 4212346 + ... + 4212355.

It is an arithmetic number, because the mean of its divisors is an integer number (12637053).

Almost surely, 2^42123505 is an apocalyptic number.

It is an amenable number.

42123505 is a deficient number, since it is larger than the sum of its proper divisors (8424707).

42123505 is an equidigital number, since it uses as much as digits as its factorization.

42123505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8424706.

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 42123505 is about 6490.2623213550. The cubic root of 42123505 is about 347.9430506404.

Adding to 42123505 its reverse (50532124), we get a palindrome (92655629).

The spelling of 42123505 in words is "forty-two million, one hundred twenty-three thousand, five hundred five".