998537379840 has 2880 divisors, whose sum is σ = 4920020098560. Its totient is φ = 186856243200.

The previous prime is 998537379809. The next prime is 998537379859. The reversal of 998537379840 is 48973735899.

998537379840 is a `hidden beast` number, since 9 + 9 + 8 + 537 + 3 + 7 + 9 + 84 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (2880).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

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 191 ways as a sum of consecutive naturals, for example, 24354570220 + ... + 24354570260.

It is an arithmetic number, because the mean of its divisors is an integer number (1708340312).

Almost surely, 2^998537379840 is an apocalyptic number.

998537379840 is a gapful number since it is divisible by the number (90) 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 998537379840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2460010049280).

998537379840 is an abundant number, since it is smaller than the sum of its proper divisors (3921482718720).

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

998537379840 is a wasteful number, since it uses less digits than its factorization.

998537379840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125 (or 82 counting only the distinct ones).

The product of its (nonzero) digits is 411505920, while the sum is 72.

The spelling of 998537379840 in words is "nine hundred ninety-eight billion, five hundred thirty-seven million, three hundred seventy-nine thousand, eight hundred forty".