42718639 has 2 divisors, whose sum is σ = 42718640. Its totient is φ = 42718638.

The previous prime is 42718579. The next prime is 42718667. The reversal of 42718639 is 93681724.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 42718639 - 2¹¹ = 42716591 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42718699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21359319 + 21359320.

It is an arithmetic number, because the mean of its divisors is an integer number (21359320).

Almost surely, 2^42718639 is an apocalyptic number.

42718639 is a deficient number, since it is larger than the sum of its proper divisors (1).

42718639 is an equidigital number, since it uses as much as digits as its factorization.

42718639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72576, while the sum is 40.

The square root of 42718639 is about 6535.9497397088. The cubic root of 42718639 is about 349.5740096221.

The spelling of 42718639 in words is "forty-two million, seven hundred eighteen thousand, six hundred thirty-nine".