228202921 has 2 divisors, whose sum is σ = 228202922. Its totient is φ = 228202920.

The previous prime is 228202889. The next prime is 228202927. The reversal of 228202921 is 129202822.

228202921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 160782400 + 67420521 = 12680^2 + 8211^2 .

It is a cyclic number.

It is not a de Polignac number, because 228202921 - 2⁵ = 228202889 is a prime.

It is a super-3 number, since 3×228202921³ (a number of 26 digits) contains 333 as substring.

It is a plaindrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 228202921.

It is not a weakly prime, because it can be changed into another prime (228202927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 114101460 + 114101461.

It is an arithmetic number, because the mean of its divisors is an integer number (114101461).

Almost surely, 2^228202921 is an apocalyptic number.

It is an amenable number.

228202921 is a deficient number, since it is larger than the sum of its proper divisors (1).

228202921 is an equidigital number, since it uses as much as digits as its factorization.

228202921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 228202921 is about 15106.3867618964. The cubic root of 228202921 is about 611.0926586519.

Subtracting from 228202921 its reverse (129202822), we obtain a palindrome (99000099).

The spelling of 228202921 in words is "two hundred twenty-eight million, two hundred two thousand, nine hundred twenty-one".