18264521 has 4 divisors (see below), whose sum is σ = 19924944. Its totient is φ = 16604100.

The previous prime is 18264509. The next prime is 18264523. The reversal of 18264521 is 12546281.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12546281 = 11 ⋅1140571.

It is a cyclic number.

It is not a de Polignac number, because 18264521 - 2¹⁴ = 18248137 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18264523) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 830195 + ... + 830216.

It is an arithmetic number, because the mean of its divisors is an integer number (4981236).

Almost surely, 2^18264521 is an apocalyptic number.

18264521 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18264521 is a deficient number, since it is larger than the sum of its proper divisors (1660423).

18264521 is a wasteful number, since it uses less digits than its factorization.

18264521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1660422.

The product of its digits is 3840, while the sum is 29.

The square root of 18264521 is about 4273.7010892200. The cubic root of 18264521 is about 263.3516815003.

The spelling of 18264521 in words is "eighteen million, two hundred sixty-four thousand, five hundred twenty-one".