42000040 has 32 divisors (see below), whose sum is σ = 97551360. Its totient is φ = 16257600.

The previous prime is 42000037. The next prime is 42000059. The reversal of 42000040 is 4000024.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 41999990 and 42000026.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15696 + ... + 18175.

It is an arithmetic number, because the mean of its divisors is an integer number (3048480).

Almost surely, 2^42000040 is an apocalyptic number.

42000040 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

42000040 is an abundant number, since it is smaller than the sum of its proper divisors (55551320).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

42000040 is a wasteful number, since it uses less digits than its factorization.

42000040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33913 (or 33909 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 10.

The square root of 42000040 is about 6480.7437844741. The cubic root of 42000040 is about 347.6027748387.

Adding to 42000040 its reverse (4000024), we get a palindrome (46000064).

The spelling of 42000040 in words is "forty-two million, forty", and thus it is an aban number, an eban number, and an uban number.