18491648 has 72 divisors (see below), whose sum is σ = 44739072. Its totient is φ = 7446528.

The previous prime is 18491639. The next prime is 18491651. The reversal of 18491648 is 84619481.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30161 + ... + 30767.

It is an arithmetic number, because the mean of its divisors is an integer number (621376).

Almost surely, 2^18491648 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 18491648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22369536).

18491648 is an abundant number, since it is smaller than the sum of its proper divisors (26247424).

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

18491648 is an equidigital number, since it uses as much as digits as its factorization.

18491648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 647 (or 633 counting only the distinct ones).

The product of its digits is 55296, while the sum is 41.

The square root of 18491648 is about 4300.1916236373. The cubic root of 18491648 is about 264.4388171850.

The spelling of 18491648 in words is "eighteen million, four hundred ninety-one thousand, six hundred forty-eight".