18474021 has 16 divisors (see below), whose sum is σ = 27835200. Its totient is φ = 12106224.

The previous prime is 18474017. The next prime is 18474059. The reversal of 18474021 is 12047481.

It is not a de Polignac number, because 18474021 - 2² = 18474017 is a prime.

It is a super-3 number, since 3×18474021³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18474091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4206 + ... + 7391.

It is an arithmetic number, because the mean of its divisors is an integer number (1739700).

Almost surely, 2^18474021 is an apocalyptic number.

It is an amenable number.

18474021 is a deficient number, since it is larger than the sum of its proper divisors (9361179).

18474021 is a wasteful number, since it uses less digits than its factorization.

18474021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11665 (or 11659 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 18474021 is about 4298.1415751462. The cubic root of 18474021 is about 264.3547658172.

The spelling of 18474021 in words is "eighteen million, four hundred seventy-four thousand, twenty-one".