228563921 has 2 divisors, whose sum is σ = 228563922. Its totient is φ = 228563920.

The previous prime is 228563887. The next prime is 228563927. The reversal of 228563921 is 129365822.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 217267600 + 11296321 = 14740^2 + 3361^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-228563921 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (228563927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 114281960 + 114281961.

It is an arithmetic number, because the mean of its divisors is an integer number (114281961).

Almost surely, 2^228563921 is an apocalyptic number.

It is an amenable number.

228563921 is a deficient number, since it is larger than the sum of its proper divisors (1).

228563921 is an equidigital number, since it uses as much as digits as its factorization.

228563921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 38.

The square root of 228563921 is about 15118.3306287434. The cubic root of 228563921 is about 611.4147232196.

The spelling of 228563921 in words is "two hundred twenty-eight million, five hundred sixty-three thousand, nine hundred twenty-one".