18545521 has 8 divisors (see below), whose sum is σ = 20490624. Its totient is φ = 16695360.

The previous prime is 18545507. The next prime is 18545531. The reversal of 18545521 is 12554581.

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

It is not a de Polignac number, because 18545521 - 2¹³ = 18537329 is a prime.

It is a super-2 number, since 2×18545521² = 687872698322882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18545531) 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, 23325 + ... + 24106.

It is an arithmetic number, because the mean of its divisors is an integer number (2561328).

Almost surely, 2^18545521 is an apocalyptic number.

It is an amenable number.

18545521 is a deficient number, since it is larger than the sum of its proper divisors (1945103).

18545521 is a wasteful number, since it uses less digits than its factorization.

18545521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47471.

The product of its digits is 8000, while the sum is 31.

The square root of 18545521 is about 4306.4510910958. The cubic root of 18545521 is about 264.6953708467.

The spelling of 18545521 in words is "eighteen million, five hundred forty-five thousand, five hundred twenty-one".