42871681 has 4 divisors (see below), whose sum is σ = 42886912. Its totient is φ = 42856452.

The previous prime is 42871663. The next prime is 42871687. The reversal of 42871681 is 18617824.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 42871681 - 2¹³ = 42863489 is a prime.

It is a super-2 number, since 2×42871681² = 3675962063531522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 42871681.

It is not an unprimeable number, because it can be changed into a prime (42871687) 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 3 ways as a sum of consecutive naturals, for example, 2025 + ... + 9478.

It is an arithmetic number, because the mean of its divisors is an integer number (10721728).

Almost surely, 2^42871681 is an apocalyptic number.

It is an amenable number.

42871681 is a deficient number, since it is larger than the sum of its proper divisors (15231).

42871681 is a wasteful number, since it uses less digits than its factorization.

42871681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15230.

The product of its digits is 21504, while the sum is 37.

The square root of 42871681 is about 6547.6469819318. The cubic root of 42871681 is about 349.9909684744.

The spelling of 42871681 in words is "forty-two million, eight hundred seventy-one thousand, six hundred eighty-one".