42420031 has 2 divisors, whose sum is σ = 42420032. Its totient is φ = 42420030.

The previous prime is 42420017. The next prime is 42420067. The reversal of 42420031 is 13002424.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 42420031 - 2⁵ = 42419999 is a prime.

It is a super-2 number, since 2×42420031² = 3598918060081922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 42419987 and 42420014.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42490031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21210015 + 21210016.

It is an arithmetic number, because the mean of its divisors is an integer number (21210016).

Almost surely, 2^42420031 is an apocalyptic number.

42420031 is a deficient number, since it is larger than the sum of its proper divisors (1).

42420031 is an equidigital number, since it uses as much as digits as its factorization.

42420031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 42420031 is about 6513.0661750054. The cubic root of 42420031 is about 348.7575840559.

Adding to 42420031 its reverse (13002424), we get a palindrome (55422455).

The spelling of 42420031 in words is "forty-two million, four hundred twenty thousand, thirty-one".