42138840 has 32 divisors (see below), whose sum is σ = 126416880. Its totient is φ = 11236992.

The previous prime is 42138799. The next prime is 42138881. The reversal of 42138840 is 4883124.

42138840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (42138799) and next prime (42138881).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 42138798 and 42138807.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 175459 + ... + 175698.

Almost surely, 2^42138840 is an apocalyptic number.

42138840 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

42138840 is an abundant number, since it is smaller than the sum of its proper divisors (84278040).

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

42138840 is a wasteful number, since it uses less digits than its factorization.

42138840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 351171 (or 351167 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 30.

The square root of 42138840 is about 6491.4435990772. The cubic root of 42138840 is about 347.9852682362.

The spelling of 42138840 in words is "forty-two million, one hundred thirty-eight thousand, eight hundred forty".