18135438 has 16 divisors (see below), whose sum is σ = 36461136. Its totient is φ = 6013440.

The previous prime is 18135437. The next prime is 18135451. The reversal of 18135438 is 83453181.

It is a super-2 number, since 2×18135438² = 657788222903688, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 18135399 and 18135408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18135437) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6673 + ... + 8988.

It is an arithmetic number, because the mean of its divisors is an integer number (2278821).

Almost surely, 2^18135438 is an apocalyptic number.

18135438 is an abundant number, since it is smaller than the sum of its proper divisors (18325698).

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

18135438 is a wasteful number, since it uses less digits than its factorization.

18135438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15859.

The product of its digits is 11520, while the sum is 33.

The square root of 18135438 is about 4258.5722959696. The cubic root of 18135438 is about 262.7298087298.

The spelling of 18135438 in words is "eighteen million, one hundred thirty-five thousand, four hundred thirty-eight".