42171804 has 36 divisors (see below), whose sum is σ = 106799784. Its totient is φ = 14031072.

The previous prime is 42171791. The next prime is 42171809. The reversal of 42171804 is 40817124.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×42171804² = 3556922105228832, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42171809) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33474 + ... + 34710.

Almost surely, 2^42171804 is an apocalyptic number.

It is an amenable number.

42171804 is an abundant number, since it is smaller than the sum of its proper divisors (64627980).

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

42171804 is a wasteful number, since it uses less digits than its factorization.

42171804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2194 (or 2189 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 42171804 is about 6493.9821373330. The cubic root of 42171804 is about 348.0759842007.

Adding to 42171804 its reverse (40817124), we get a palindrome (82988928).

The spelling of 42171804 in words is "forty-two million, one hundred seventy-one thousand, eight hundred four".