17940042 has 80 divisors (see below), whose sum is σ = 42871752. Its totient is φ = 5598720.

The previous prime is 17940017. The next prime is 17940059. The reversal of 17940042 is 24004971.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 15046641 + 2893401 = 3879^2 + 1701^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 17939988 and 17940015.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 245718 + ... + 245790.

Almost surely, 2^17940042 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 17940042, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21435876).

17940042 is an abundant number, since it is smaller than the sum of its proper divisors (24931710).

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

17940042 is a wasteful number, since it uses less digits than its factorization.

17940042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165 (or 156 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 17940042 is about 4235.5686749243. The cubic root of 17940042 is about 261.7828260733.

The spelling of 17940042 in words is "seventeen million, nine hundred forty thousand, forty-two".