42172389 has 18 divisors (see below), whose sum is σ = 70861830. Its totient is φ = 24098256.

The previous prime is 42172373. The next prime is 42172397. The reversal of 42172389 is 98327124.

It can be written as a sum of positive squares in only one way, i.e., 22724289 + 19448100 = 4767^2 + 4410^2 .

It is not a de Polignac number, because 42172389 - 2⁴ = 42172373 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42172309) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 47374 + ... + 48255.

Almost surely, 2^42172389 is an apocalyptic number.

42172389 is a gapful number since it is divisible by the number (49) formed by its first and last digit.

It is an amenable number.

42172389 is a deficient number, since it is larger than the sum of its proper divisors (28689441).

42172389 is a wasteful number, since it uses less digits than its factorization.

42172389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95649 (or 95639 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 42172389 is about 6494.0271788775. The cubic root of 42172389 is about 348.0775936766.

The spelling of 42172389 in words is "forty-two million, one hundred seventy-two thousand, three hundred eighty-nine".