42981 has 4 divisors (see below), whose sum is σ = 57312. Its totient is φ = 28652.

The previous prime is 42979. The next prime is 42989. The reversal of 42981 is 18924.

42981 is nontrivially palindromic in base 2.

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 42981 - 2¹ = 42979 is a prime.

It is a super-2 number, since 2×42981² = 3694732722, which contains 22 as substring.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7161 + ... + 7166.

It is an arithmetic number, because the mean of its divisors is an integer number (14328).

2⁴²⁹⁸¹ is an apocalyptic number.

It is an amenable number.

42981 is a deficient number, since it is larger than the sum of its proper divisors (14331).

42981 is a wasteful number, since it uses less digits than its factorization.

42981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14330.

The product of its digits is 576, while the sum is 24.

The square root of 42981 is about 207.3185954033. The cubic root of 42981 is about 35.0288198000.

The spelling of 42981 in words is "forty-two thousand, nine hundred eighty-one".