18019690 has 32 divisors (see below), whose sum is σ = 35315280. Its totient is φ = 6580224.

The previous prime is 18019669. The next prime is 18019691. The reversal of 18019690 is 9691081.

It can be written as a sum of positive squares in 8 ways, for example, as 954529 + 17065161 = 977^2 + 4131^2 .

It is a super-2 number, since 2×18019690² = 649418455392200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18019691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11896 + ... + 13324.

Almost surely, 2^18019690 is an apocalyptic number.

18019690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18019690 is a deficient number, since it is larger than the sum of its proper divisors (17295590).

18019690 is a wasteful number, since it uses less digits than its factorization.

18019690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1546.

The product of its (nonzero) digits is 3888, while the sum is 34.

The square root of 18019690 is about 4244.9605416305. The cubic root of 18019690 is about 262.1696645944.

The spelling of 18019690 in words is "eighteen million, nineteen thousand, six hundred ninety".