18731008 has 52 divisors (see below), whose sum is σ = 39808260. Its totient is φ = 8781824.

The previous prime is 18730981. The next prime is 18731021. The reversal of 18731008 is 80013781.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 7225344 + 11505664 = 2688^2 + 3392^2 .

It is a super-4 number, since 4×18731008⁴ (a number of 30 digits) contains 4444 as substring.

It is a zygodrome in base 16.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69498 + ... + 69766.

Almost surely, 2^18731008 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18731008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19904130).

18731008 is an abundant number, since it is smaller than the sum of its proper divisors (21077252).

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

18731008 is an equidigital number, since it uses as much as digits as its factorization.

18731008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 310 (or 288 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 28.

The square root of 18731008 is about 4327.9334560504. The cubic root of 18731008 is about 265.5749141643.

Adding to 18731008 its reverse (80013781), we get a palindrome (98744789).

The spelling of 18731008 in words is "eighteen million, seven hundred thirty-one thousand, eight".