42939139 has 2 divisors, whose sum is σ = 42939140. Its totient is φ = 42939138.

The previous prime is 42939131. The next prime is 42939179. The reversal of 42939139 is 93193924.

It is an a-pointer prime, because the next prime (42939179) can be obtained adding 42939139 to its sum of digits (40).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 42939139 - 2³ = 42939131 is a prime.

It is a super-2 number, since 2×42939139² = 3687539316122642, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (42939131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21469569 + 21469570.

It is an arithmetic number, because the mean of its divisors is an integer number (21469570).

Almost surely, 2^42939139 is an apocalyptic number.

42939139 is a deficient number, since it is larger than the sum of its proper divisors (1).

42939139 is an equidigital number, since it uses as much as digits as its factorization.

42939139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 52488, while the sum is 40.

The square root of 42939139 is about 6552.7962733477. The cubic root of 42939139 is about 350.1744409349.

The spelling of 42939139 in words is "forty-two million, nine hundred thirty-nine thousand, one hundred thirty-nine".