17949981931924 has 144 divisors (see below), whose sum is σ = 38121199618320. Its totient is φ = 7367576832000.

The previous prime is 17949981931867. The next prime is 17949981931939. The reversal of 17949981931924 is 42913918994971.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 5685277521924 + 12264704410000 = 2384382^2 + 3502100^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 249473794 + ... + 249545734.

It is an arithmetic number, because the mean of its divisors is an integer number (264730552905).

Almost surely, 2^{17949981931924} is an apocalyptic number.

17949981931924 is a gapful number since it is divisible by the number (14) 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 17949981931924, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19060599809160).

17949981931924 is an abundant number, since it is smaller than the sum of its proper divisors (20171217686396).

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

17949981931924 is a wasteful number, since it uses less digits than its factorization.

17949981931924 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72570 (or 72561 counting only the distinct ones).

The product of its digits is 317447424, while the sum is 76.

The spelling of 17949981931924 in words is "seventeen trillion, nine hundred forty-nine billion, nine hundred eighty-one million, nine hundred thirty-one thousand, nine hundred twenty-four".