42129923 has 4 divisors (see below), whose sum is σ = 45959928. Its totient is φ = 38299920.

The previous prime is 42129911. The next prime is 42129929. The reversal of 42129923 is 32992124.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 42129923 - 2¹⁰ = 42128899 is a prime.

It is a super-3 number, since 3×42129923³ (a number of 24 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 42129923.

It is not an unprimeable number, because it can be changed into a prime (42129929) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1914986 + ... + 1915007.

It is an arithmetic number, because the mean of its divisors is an integer number (11489982).

Almost surely, 2^42129923 is an apocalyptic number.

42129923 is a deficient number, since it is larger than the sum of its proper divisors (3830005).

42129923 is a wasteful number, since it uses less digits than its factorization.

42129923 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3830004.

The product of its digits is 7776, while the sum is 32.

The square root of 42129923 is about 6490.7567355432. The cubic root of 42129923 is about 347.9607207836.

The spelling of 42129923 in words is "forty-two million, one hundred twenty-nine thousand, nine hundred twenty-three".