42439815 has 32 divisors (see below), whose sum is σ = 82310400. Its totient is φ = 20576160.

The previous prime is 42439783. The next prime is 42439823. The reversal of 42439815 is 51893424.

It is not a de Polignac number, because 42439815 - 2⁵ = 42439783 is a prime.

It is a super-2 number, since 2×42439815² = 3602275794468450, which contains 22 as substring.

It is a nialpdrome in base 9.

It is a self number, because there is not a number n which added to its sum of digits gives 42439815.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12805 + ... + 15774.

It is an arithmetic number, because the mean of its divisors is an integer number (2572200).

Almost surely, 2^42439815 is an apocalyptic number.

42439815 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

42439815 is a deficient number, since it is larger than the sum of its proper divisors (39870585).

42439815 is a wasteful number, since it uses less digits than its factorization.

42439815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28604 (or 28598 counting only the distinct ones).

The product of its digits is 34560, while the sum is 36.

The square root of 42439815 is about 6514.5847910669. The cubic root of 42439815 is about 348.8117938832.

The spelling of 42439815 in words is "forty-two million, four hundred thirty-nine thousand, eight hundred fifteen".