18019620 has 36 divisors (see below), whose sum is σ = 54660060. Its totient is φ = 4805184.

The previous prime is 18019607. The next prime is 18019621. The reversal of 18019620 is 2691081.

It can be written as a sum of positive squares in 2 ways, for example, as 3594816 + 14424804 = 1896^2 + 3798^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (18019621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 49875 + ... + 50234.

It is an arithmetic number, because the mean of its divisors is an integer number (1518335).

Almost surely, 2^18019620 is an apocalyptic number.

18019620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18019620 is an abundant number, since it is smaller than the sum of its proper divisors (36640440).

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

18019620 is a wasteful number, since it uses less digits than its factorization.

18019620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100124 (or 100119 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 18019620 is about 4244.9522965518. The cubic root of 18019620 is about 262.1693251158.

The spelling of 18019620 in words is "eighteen million, nineteen thousand, six hundred twenty".