18998657280 has 216 divisors, whose sum is σ = 65978541720. Its totient is φ = 5047418880.

The previous prime is 18998657269. The next prime is 18998657281. The reversal of 18998657280 is 8275689981.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 585252864 + 18413404416 = 24192^2 + 135696^2 .

It is not an unprimeable number, because it can be changed into a prime (18998657281) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3234186 + ... + 3240054.

Almost surely, 2^18998657280 is an apocalyptic number.

18998657280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18998657280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32989270860).

18998657280 is an abundant number, since it is smaller than the sum of its proper divisors (46979884440).

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

18998657280 is a wasteful number, since it uses less digits than its factorization.

18998657280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6177 (or 6160 counting only the distinct ones).

The product of its (nonzero) digits is 17418240, while the sum is 63.

The spelling of 18998657280 in words is "eighteen billion, nine hundred ninety-eight million, six hundred fifty-seven thousand, two hundred eighty".