42100031 has 2 divisors, whose sum is σ = 42100032. Its totient is φ = 42100030.

The previous prime is 42100027. The next prime is 42100033. The reversal of 42100031 is 13000124.

It is a happy number.

42100031 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 42100031 - 2² = 42100027 is a prime.

It is a super-2 number, since 2×42100031² = 3544825220401922, which contains 22 as substring.

Together with 42100033, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 42099985 and 42100021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42100033) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21050015 + 21050016.

It is an arithmetic number, because the mean of its divisors is an integer number (21050016).

Almost surely, 2^42100031 is an apocalyptic number.

42100031 is a deficient number, since it is larger than the sum of its proper divisors (1).

42100031 is an equidigital number, since it uses as much as digits as its factorization.

42100031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 42100031 is about 6488.4536678626. The cubic root of 42100031 is about 347.8784063456.

Adding to 42100031 its reverse (13000124), we get a palindrome (55100155).

The spelling of 42100031 in words is "forty-two million, one hundred thousand, thirty-one".