42172551 has 24 divisors (see below), whose sum is σ = 63423360. Its totient is φ = 26981136.

The previous prime is 42172541. The next prime is 42172591. The reversal of 42172551 is 15527124.

42172551 is a `hidden beast` number, since 42 + 1 + 72 + 551 = 666.

It is not a de Polignac number, because 42172551 - 2⁵ = 42172519 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42172511) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21910 + ... + 23756.

It is an arithmetic number, because the mean of its divisors is an integer number (2642640).

Almost surely, 2^42172551 is an apocalyptic number.

42172551 is a deficient number, since it is larger than the sum of its proper divisors (21250809).

42172551 is a wasteful number, since it uses less digits than its factorization.

42172551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1955 (or 1952 counting only the distinct ones).

The product of its digits is 2800, while the sum is 27.

The square root of 42172551 is about 6494.0396518654. The cubic root of 42172551 is about 348.0780393750.

Adding to 42172551 its reverse (15527124), we get a palindrome (57699675).

The spelling of 42172551 in words is "forty-two million, one hundred seventy-two thousand, five hundred fifty-one".