17981942 has 16 divisors (see below), whose sum is σ = 30974400. Its totient is φ = 7743240.

The previous prime is 17981933. The next prime is 17981947. The reversal of 17981942 is 24918971.

It is a self number, because there is not a number n which added to its sum of digits gives 17981942.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (17981947) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21092 + ... + 21927.

It is an arithmetic number, because the mean of its divisors is an integer number (1935900).

Almost surely, 2^17981942 is an apocalyptic number.

17981942 is a deficient number, since it is larger than the sum of its proper divisors (12992458).

17981942 is a wasteful number, since it uses less digits than its factorization.

17981942 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43051.

The product of its digits is 36288, while the sum is 41.

The square root of 17981942 is about 4240.5119973890. The cubic root of 17981942 is about 261.9864705637.

The spelling of 17981942 in words is "seventeen million, nine hundred eighty-one thousand, nine hundred forty-two".