18720525 has 12 divisors (see below), whose sum is σ = 30951392. Its totient is φ = 9984240.

The previous prime is 18720467. The next prime is 18720539. The reversal of 18720525 is 52502781.

It is not a de Polignac number, because 18720525 - 2¹⁶ = 18654989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18720492 and 18720501.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 124729 + ... + 124878.

Almost surely, 2^18720525 is an apocalyptic number.

18720525 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18720525 is a deficient number, since it is larger than the sum of its proper divisors (12230867).

18720525 is a wasteful number, since it uses less digits than its factorization.

18720525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249620 (or 249615 counting only the distinct ones).

The product of its (nonzero) digits is 5600, while the sum is 30.

The square root of 18720525 is about 4326.7222004654. The cubic root of 18720525 is about 265.5253610142.

The spelling of 18720525 in words is "eighteen million, seven hundred twenty thousand, five hundred twenty-five".