42009101 has 2 divisors, whose sum is σ = 42009102. Its totient is φ = 42009100.

The previous prime is 42009083. The next prime is 42009127. The reversal of 42009101 is 10190024.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40386025 + 1623076 = 6355^2 + 1274^2 .

It is a cyclic number.

It is not a de Polignac number, because 42009101 - 2²² = 37814797 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 42009101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42009131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21004550 + 21004551.

It is an arithmetic number, because the mean of its divisors is an integer number (21004551).

Almost surely, 2^42009101 is an apocalyptic number.

It is an amenable number.

42009101 is a deficient number, since it is larger than the sum of its proper divisors (1).

42009101 is an equidigital number, since it uses as much as digits as its factorization.

42009101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 42009101 is about 6481.4428177683. The cubic root of 42009101 is about 347.6277700710.

Adding to 42009101 its reverse (10190024), we get a palindrome (52199125).

The spelling of 42009101 in words is "forty-two million, nine thousand, one hundred one".