15840138 has 8 divisors (see below), whose sum is σ = 31680288. Its totient is φ = 5280044.

The previous prime is 15840113. The next prime is 15840193. The reversal of 15840138 is 83104851.

It is a sphenic number, since it is the product of 3 distinct primes.

15840138 is an admirable 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 3 ways as a sum of consecutive naturals, for example, 1320006 + ... + 1320017.

It is an arithmetic number, because the mean of its divisors is an integer number (3960036).

Almost surely, 2^15840138 is an apocalyptic number.

15840138 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

15840138 is a wasteful number, since it uses less digits than its factorization.

15840138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2640028.

The product of its (nonzero) digits is 3840, while the sum is 30.

The square root of 15840138 is about 3979.9670852910. The cubic root of 15840138 is about 251.1421764516.

Adding to 15840138 its reverse (83104851), we get a palindrome (98944989).

The spelling of 15840138 in words is "fifteen million, eight hundred forty thousand, one hundred thirty-eight".