42172542 has 16 divisors (see below), whose sum is σ = 93716880. Its totient is φ = 14057496.

The previous prime is 42172541. The next prime is 42172591. The reversal of 42172542 is 24527124.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42172541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 390433 + ... + 390540.

It is an arithmetic number, because the mean of its divisors is an integer number (5857305).

Almost surely, 2^42172542 is an apocalyptic number.

42172542 is an abundant number, since it is smaller than the sum of its proper divisors (51544338).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

42172542 is a wasteful number, since it uses less digits than its factorization.

42172542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 780984 (or 780978 counting only the distinct ones).

The product of its digits is 4480, while the sum is 27.

The square root of 42172542 is about 6494.0389589223. The cubic root of 42172542 is about 348.0780146140.

Adding to 42172542 its reverse (24527124), we get a palindrome (66699666).

The spelling of 42172542 in words is "forty-two million, one hundred seventy-two thousand, five hundred forty-two".