228028421 has 8 divisors (see below), whose sum is σ = 239125080. Its totient is φ = 217147392.

The previous prime is 228028399. The next prime is 228028433. The reversal of 228028421 is 124820822.

It can be written as a sum of positive squares in 4 ways, for example, as 105062500 + 122965921 = 10250^2 + 11089^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 228028421 - 2²⁶ = 160919557 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (228028121) 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, 51740 + ... + 55973.

It is an arithmetic number, because the mean of its divisors is an integer number (29890635).

Almost surely, 2^228028421 is an apocalyptic number.

It is an amenable number.

228028421 is a deficient number, since it is larger than the sum of its proper divisors (11096659).

228028421 is a wasteful number, since it uses less digits than its factorization.

228028421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107815.

The product of its (nonzero) digits is 4096, while the sum is 29.

The square root of 228028421 is about 15100.6099545681. The cubic root of 228028421 is about 610.9368574606.

The spelling of 228028421 in words is "two hundred twenty-eight million, twenty-eight thousand, four hundred twenty-one".