18604421 has 12 divisors (see below), whose sum is σ = 20631744. Its totient is φ = 16637400.

The previous prime is 18604393. The next prime is 18604427. The reversal of 18604421 is 12440681.

It is not a de Polignac number, because 18604421 - 2¹⁰ = 18603397 is a prime.

It is a super-2 number, since 2×18604421² = 692248961490482, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18604427) 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, 68516 + ... + 68786.

It is an arithmetic number, because the mean of its divisors is an integer number (1719312).

Almost surely, 2^18604421 is an apocalyptic number.

18604421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18604421 is a deficient number, since it is larger than the sum of its proper divisors (2027323).

18604421 is an equidigital number, since it uses as much as digits as its factorization.

18604421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 440 (or 361 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 18604421 is about 4313.2842475311. The cubic root of 18604421 is about 264.9752961426.

The spelling of 18604421 in words is "eighteen million, six hundred four thousand, four hundred twenty-one".