42171808 has 48 divisors (see below), whose sum is σ = 96223680. Its totient is φ = 17819136.

The previous prime is 42171791. The next prime is 42171809. The reversal of 42171808 is 80817124.

It is a super-2 number, since 2×42171808² = 3556922779977728, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 42171808.

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 7 ways as a sum of consecutive naturals, for example, 15063 + ... + 17641.

It is an arithmetic number, because the mean of its divisors is an integer number (2004660).

Almost surely, 2^42171808 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 42171808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48111840).

42171808 is an abundant number, since it is smaller than the sum of its proper divisors (54051872).

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

42171808 is a wasteful number, since it uses less digits than its factorization.

42171808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2669 (or 2661 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 31.

The square root of 42171808 is about 6493.9824453104. The cubic root of 42171808 is about 348.0759952057.

The spelling of 42171808 in words is "forty-two million, one hundred seventy-one thousand, eight hundred eight".