18220449 has 32 divisors (see below), whose sum is σ = 28026880. Its totient is φ = 10435392.

The previous prime is 18220429. The next prime is 18220451. The reversal of 18220449 is 94402281.

It is not a de Polignac number, because 18220449 - 2⁵ = 18220417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18220429) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 49464 + ... + 49830.

It is an arithmetic number, because the mean of its divisors is an integer number (875840).

Almost surely, 2^18220449 is an apocalyptic number.

18220449 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

18220449 is a deficient number, since it is larger than the sum of its proper divisors (9806431).

18220449 is a wasteful number, since it uses less digits than its factorization.

18220449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 469.

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 18220449 is about 4268.5417884800. The cubic root of 18220449 is about 263.1396897519.

The spelling of 18220449 in words is "eighteen million, two hundred twenty thousand, four hundred forty-nine".