218490420 has 24 divisors (see below), whose sum is σ = 611773344. Its totient is φ = 58264096.

The previous prime is 218490413. The next prime is 218490421. The reversal of 218490420 is 24094812.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218490421) 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 7 ways as a sum of consecutive naturals, for example, 1820694 + ... + 1820813.

It is an arithmetic number, because the mean of its divisors is an integer number (25490556).

Almost surely, 2^218490420 is an apocalyptic number.

218490420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

218490420 is an abundant number, since it is smaller than the sum of its proper divisors (393282924).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

218490420 is a wasteful number, since it uses less digits than its factorization.

218490420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3641519 (or 3641517 counting only the distinct ones).

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

The square root of 218490420 is about 14781.4214472087. The cubic root of 218490420 is about 602.2971384787.

The spelling of 218490420 in words is "two hundred eighteen million, four hundred ninety thousand, four hundred twenty".