42172006 has 4 divisors (see below), whose sum is σ = 63258012. Its totient is φ = 21086002.

The previous prime is 42171989. The next prime is 42172007. The reversal of 42172006 is 60027124.

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

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42172007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10543000 + ... + 10543003.

It is an arithmetic number, because the mean of its divisors is an integer number (15814503).

Almost surely, 2^42172006 is an apocalyptic number.

42172006 is a deficient number, since it is larger than the sum of its proper divisors (21086006).

42172006 is a wasteful number, since it uses less digits than its factorization.

42172006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21086005.

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 42172006 is about 6493.9976901751. The cubic root of 42172006 is about 348.0765399530.

It can be divided in two parts, 421 and 72006, that added together give a palindrome (72427).

The spelling of 42172006 in words is "forty-two million, one hundred seventy-two thousand, six".