18648381 has 8 divisors (see below), whose sum is σ = 24884704. Its totient is φ = 12422160.

The previous prime is 18648373. The next prime is 18648401. The reversal of 18648381 is 18384681.

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

It is not a de Polignac number, because 18648381 - 2³ = 18648373 is a prime.

It is a super-2 number, since 2×18648381² = 695524227842322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18648181) by changing a digit.

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, 4935 + ... + 7851.

It is an arithmetic number, because the mean of its divisors is an integer number (3110588).

Almost surely, 2^18648381 is an apocalyptic number.

It is an amenable number.

18648381 is a deficient number, since it is larger than the sum of its proper divisors (6236323).

18648381 is a wasteful number, since it uses less digits than its factorization.

18648381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5051.

The product of its digits is 36864, while the sum is 39.

The square root of 18648381 is about 4318.3771257267. The cubic root of 18648381 is about 265.1838335206.

The spelling of 18648381 in words is "eighteen million, six hundred forty-eight thousand, three hundred eighty-one".