17918125440 has 128 divisors (see below), whose sum is σ = 57236198400. Its totient is φ = 4767946752.

The previous prime is 17918125439. The next prime is 17918125441. The reversal of 17918125440 is 4452181971.

It is an interprime number because it is at equal distance from previous prime (17918125439) and next prime (17918125441).

It is a tau number, because it is divible by the number of its divisors (128).

It is a junction number, because it is equal to n+sod(n) for n = 17918125392 and 17918125401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (17918125441) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 909939 + ... + 929421.

It is an arithmetic number, because the mean of its divisors is an integer number (447157800).

Almost surely, 2^17918125440 is an apocalyptic number.

17918125440 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 17918125440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28618099200).

17918125440 is an abundant number, since it is smaller than the sum of its proper divisors (39318072960).

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

17918125440 is a wasteful number, since it uses less digits than its factorization.

17918125440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19984 (or 19972 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 42.

The spelling of 17918125440 in words is "seventeen billion, nine hundred eighteen million, one hundred twenty-five thousand, four hundred forty".