18022405 has 4 divisors (see below), whose sum is σ = 21626892. Its totient is φ = 14417920.

The previous prime is 18022399. The next prime is 18022429. The reversal of 18022405 is 50422081.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50422081 = 1597 ⋅31573.

It can be written as a sum of positive squares in 2 ways, for example, as 13498276 + 4524129 = 3674^2 + 2127^2 .

It is not a de Polignac number, because 18022405 - 2²¹ = 15925253 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1802236 + ... + 1802245.

It is an arithmetic number, because the mean of its divisors is an integer number (5406723).

Almost surely, 2^18022405 is an apocalyptic number.

It is an amenable number.

18022405 is a deficient number, since it is larger than the sum of its proper divisors (3604487).

18022405 is an equidigital number, since it uses as much as digits as its factorization.

18022405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3604486.

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 18022405 is about 4245.2803205442. The cubic root of 18022405 is about 262.1828308382.

Adding to 18022405 its reverse (50422081), we get a palindrome (68444486).

The spelling of 18022405 in words is "eighteen million, twenty-two thousand, four hundred five".