17989990 has 8 divisors (see below), whose sum is σ = 32382000. Its totient is φ = 7195992.

The previous prime is 17989987. The next prime is 17989999. The reversal of 17989990 is 9998971.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (17989999) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 899490 + ... + 899509.

It is an arithmetic number, because the mean of its divisors is an integer number (4047750).

Almost surely, 2^17989990 is an apocalyptic number.

17989990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

17989990 is a deficient number, since it is larger than the sum of its proper divisors (14392010).

17989990 is a wasteful number, since it uses less digits than its factorization.

17989990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1799006.

The product of its (nonzero) digits is 367416, while the sum is 52.

The square root of 17989990 is about 4241.4608332507. The cubic root of 17989990 is about 262.0255496324.

The spelling of 17989990 in words is "seventeen million, nine hundred eighty-nine thousand, nine hundred ninety".