18407121 has 4 divisors (see below), whose sum is σ = 24542832. Its totient is φ = 12271412.

The previous prime is 18407117. The next prime is 18407131. The reversal of 18407121 is 12170481.

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 18407121 - 2² = 18407117 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18407091 and 18407100.

It is not an unprimeable number, because it can be changed into a prime (18407131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3067851 + ... + 3067856.

It is an arithmetic number, because the mean of its divisors is an integer number (6135708).

Almost surely, 2^18407121 is an apocalyptic number.

It is an amenable number.

18407121 is a deficient number, since it is larger than the sum of its proper divisors (6135711).

18407121 is an equidigital number, since it uses as much as digits as its factorization.

18407121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6135710.

The product of its (nonzero) digits is 448, while the sum is 24.

The square root of 18407121 is about 4290.3520834542. The cubic root of 18407121 is about 264.0352770811.

It can be divided in two parts, 18407 and 121, that added together give a triangular number (18528 = T₁₉₂).

The spelling of 18407121 in words is "eighteen million, four hundred seven thousand, one hundred twenty-one".