18481938 has 16 divisors (see below), whose sum is σ = 37061760. Its totient is φ = 6144336.

The previous prime is 18481937. The next prime is 18481943. The reversal of 18481938 is 83918481.

It is a self number, because there is not a number n which added to its sum of digits gives 18481938.

It is not an unprimeable number, because it can be changed into a prime (18481937) 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, 1498 + ... + 6261.

It is an arithmetic number, because the mean of its divisors is an integer number (2316360).

Almost surely, 2^18481938 is an apocalyptic number.

18481938 is an abundant number, since it is smaller than the sum of its proper divisors (18579822).

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

18481938 is a wasteful number, since it uses less digits than its factorization.

18481938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8161.

The product of its digits is 55296, while the sum is 42.

The square root of 18481938 is about 4299.0624559315. The cubic root of 18481938 is about 264.3925233035.

The spelling of 18481938 in words is "eighteen million, four hundred eighty-one thousand, nine hundred thirty-eight".