18491018490 has 192 divisors, whose sum is σ = 58600039680. Its totient is φ = 3948963840.

The previous prime is 18491018449. The next prime is 18491018537. The reversal of 18491018490 is 9481019481.

18491018490 is a `hidden beast` number, since 18 + 49 + 101 + 8 + 490 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1482480 + ... + 1494900.

It is an arithmetic number, because the mean of its divisors is an integer number (305208540).

Almost surely, 2^18491018490 is an apocalyptic number.

18491018490 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 18491018490, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29300019840).

18491018490 is an abundant number, since it is smaller than the sum of its proper divisors (40109021190).

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

18491018490 is a wasteful number, since it uses less digits than its factorization.

18491018490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12597 (or 12594 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 45.

Subtracting from 18491018490 its reverse (9481019481), we obtain a palindrome (9009999009).

The spelling of 18491018490 in words is "eighteen billion, four hundred ninety-one million, eighteen thousand, four hundred ninety".