18219427 has 12 divisors (see below), whose sum is σ = 20203056. Its totient is φ = 16396160.

The previous prime is 18219407. The next prime is 18219433. The reversal of 18219427 is 72491281.

It is not a de Polignac number, because 18219427 - 2¹¹ = 18217379 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18219392 and 18219401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18219407) 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, 5277 + ... + 8017.

It is an arithmetic number, because the mean of its divisors is an integer number (1683588).

Almost surely, 2^18219427 is an apocalyptic number.

18219427 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

18219427 is a deficient number, since it is larger than the sum of its proper divisors (1983629).

18219427 is a wasteful number, since it uses less digits than its factorization.

18219427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2798 (or 2781 counting only the distinct ones).

The product of its digits is 8064, while the sum is 34.

The square root of 18219427 is about 4268.4220737879. The cubic root of 18219427 is about 263.1347697525.

The spelling of 18219427 in words is "eighteen million, two hundred nineteen thousand, four hundred twenty-seven".