42000019 has 2 divisors, whose sum is σ = 42000020. Its totient is φ = 42000018.

The previous prime is 42000017. The next prime is 42000029. The reversal of 42000019 is 91000024.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 42000019 - 2¹ = 42000017 is a prime.

It is a super-2 number, since 2×42000019² = 3528003192000722, which contains 22 as substring.

Together with 42000017, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 41999966 and 42000011.

It is not a weakly prime, because it can be changed into another prime (42000011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21000009 + 21000010.

It is an arithmetic number, because the mean of its divisors is an integer number (21000010).

Almost surely, 2^42000019 is an apocalyptic number.

42000019 is a deficient number, since it is larger than the sum of its proper divisors (1).

42000019 is an equidigital number, since it uses as much as digits as its factorization.

42000019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 42000019 is about 6480.7421642895. The cubic root of 42000019 is about 347.6027169049.

The spelling of 42000019 in words is "forty-two million, nineteen", and thus it is an aban number and an uban number.