42171909 has 8 divisors (see below), whose sum is σ = 60554592. Its totient is φ = 25951920.

The previous prime is 42171907. The next prime is 42171929. The reversal of 42171909 is 90917124.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 42171909 - 2¹ = 42171907 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 42171909.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42171907) 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, 540627 + ... + 540704.

It is an arithmetic number, because the mean of its divisors is an integer number (7569324).

Almost surely, 2^42171909 is an apocalyptic number.

It is an amenable number.

42171909 is a deficient number, since it is larger than the sum of its proper divisors (18382683).

42171909 is a wasteful number, since it uses less digits than its factorization.

42171909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1081347.

The product of its (nonzero) digits is 4536, while the sum is 33.

The square root of 42171909 is about 6493.9902217358. The cubic root of 42171909 is about 348.0762730821.

The spelling of 42171909 in words is "forty-two million, one hundred seventy-one thousand, nine hundred nine".