228021999 has 16 divisors (see below), whose sum is σ = 308582400. Its totient is φ = 149749056.

The previous prime is 228021979. The next prime is 228022007. The reversal of 228021999 is 999120822.

It is a happy number.

It is not a de Polignac number, because 228021999 - 2¹¹ = 228019951 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 228021999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (228021919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100722 + ... + 102960.

It is an arithmetic number, because the mean of its divisors is an integer number (19286400).

Almost surely, 2^228021999 is an apocalyptic number.

228021999 is a deficient number, since it is larger than the sum of its proper divisors (80560401).

228021999 is a wasteful number, since it uses less digits than its factorization.

228021999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2734.

The product of its (nonzero) digits is 46656, while the sum is 42.

The square root of 228021999 is about 15100.3973126537. The cubic root of 228021999 is about 610.9311221034.

The spelling of 228021999 in words is "two hundred twenty-eight million, twenty-one thousand, nine hundred ninety-nine".