18775521 has 12 divisors (see below), whose sum is σ = 28299648. Its totient is φ = 11972664.

The previous prime is 18775507. The next prime is 18775571. The reversal of 18775521 is 12557781.

It is not a de Polignac number, because 18775521 - 2¹¹ = 18773473 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18775501) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45145 + ... + 45558.

It is an arithmetic number, because the mean of its divisors is an integer number (2358304).

Almost surely, 2^18775521 is an apocalyptic number.

It is an amenable number.

18775521 is a deficient number, since it is larger than the sum of its proper divisors (9524127).

18775521 is a wasteful number, since it uses less digits than its factorization.

18775521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90732 (or 90729 counting only the distinct ones).

The product of its digits is 19600, while the sum is 36.

The square root of 18775521 is about 4333.0729280731. The cubic root of 18775521 is about 265.7851214693.

The spelling of 18775521 in words is "eighteen million, seven hundred seventy-five thousand, five hundred twenty-one".