17998539450 has 144 divisors (see below), whose sum is σ = 47287464480. Its totient is φ = 4529831040.

The previous prime is 17998539437. The next prime is 17998539479. The reversal of 17998539450 is 5493589971.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 20522412 + ... + 20523288.

It is an arithmetic number, because the mean of its divisors is an integer number (328385170).

Almost surely, 2^17998539450 is an apocalyptic number.

17998539450 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 17998539450, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23643732240).

17998539450 is an abundant number, since it is smaller than the sum of its proper divisors (29288925030).

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

17998539450 is a wasteful number, since it uses less digits than its factorization.

17998539450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1309 (or 1285 counting only the distinct ones).

The product of its (nonzero) digits is 12247200, while the sum is 60.

The spelling of 17998539450 in words is "seventeen billion, nine hundred ninety-eight million, five hundred thirty-nine thousand, four hundred fifty".