18860521 has 4 divisors (see below), whose sum is σ = 19853200. Its totient is φ = 17867844.

The previous prime is 18860509. The next prime is 18860551. The reversal of 18860521 is 12506881.

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.

It is a cyclic number.

It is not a de Polignac number, because 18860521 - 2⁷ = 18860393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18860551) 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, 496311 + ... + 496348.

It is an arithmetic number, because the mean of its divisors is an integer number (4963300).

Almost surely, 2^18860521 is an apocalyptic number.

It is an amenable number.

18860521 is a deficient number, since it is larger than the sum of its proper divisors (992679).

18860521 is an equidigital number, since it uses as much as digits as its factorization.

18860521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 992678.

The product of its (nonzero) digits is 3840, while the sum is 31.

The square root of 18860521 is about 4342.8701339091. The cubic root of 18860521 is about 266.1856026524.

It can be divided in two parts, 188605 and 21, that multiplied together give a triangular number (3960705 = T₂₈₁₄).

The spelling of 18860521 in words is "eighteen million, eight hundred sixty thousand, five hundred twenty-one".