42973639 has 4 divisors (see below), whose sum is σ = 43003240. Its totient is φ = 42944040.

The previous prime is 42973607. The next prime is 42973681. The reversal of 42973639 is 93637924.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 42973639 - 2⁵ = 42973607 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 42973595 and 42973604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42973339) 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, 12504 + ... + 15565.

It is an arithmetic number, because the mean of its divisors is an integer number (10750810).

Almost surely, 2^42973639 is an apocalyptic number.

42973639 is a deficient number, since it is larger than the sum of its proper divisors (29601).

42973639 is a wasteful number, since it uses less digits than its factorization.

42973639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29600.

The product of its digits is 244944, while the sum is 43.

The square root of 42973639 is about 6555.4282087443. The cubic root of 42973639 is about 350.2681998720.

The spelling of 42973639 in words is "forty-two million, nine hundred seventy-three thousand, six hundred thirty-nine".