42129109 has 4 divisors (see below), whose sum is σ = 45959040. Its totient is φ = 38299180.

The previous prime is 42129107. The next prime is 42129119. The reversal of 42129109 is 90192124.

It is a happy number.

42129109 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 42129109 - 2¹ = 42129107 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42129107) 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 in 3 ways as a sum of consecutive naturals, for example, 1914949 + ... + 1914970.

It is an arithmetic number, because the mean of its divisors is an integer number (11489760).

Almost surely, 2^42129109 is an apocalyptic number.

It is an amenable number.

42129109 is a deficient number, since it is larger than the sum of its proper divisors (3829931).

42129109 is a wasteful number, since it uses less digits than its factorization.

42129109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3829930.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 42129109 is about 6490.6940306873. The cubic root of 42129109 is about 347.9584797647.

The spelling of 42129109 in words is "forty-two million, one hundred twenty-nine thousand, one hundred nine".