228505261 has 2 divisors, whose sum is σ = 228505262. Its totient is φ = 228505260.

The previous prime is 228505187. The next prime is 228505283. The reversal of 228505261 is 162505822.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 193043236 + 35462025 = 13894^2 + 5955^2 .

It is a cyclic number.

It is not a de Polignac number, because 228505261 - 2¹³ = 228497069 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (228505561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 114252630 + 114252631.

It is an arithmetic number, because the mean of its divisors is an integer number (114252631).

Almost surely, 2^228505261 is an apocalyptic number.

It is an amenable number.

228505261 is a deficient number, since it is larger than the sum of its proper divisors (1).

228505261 is an equidigital number, since it uses as much as digits as its factorization.

228505261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9600, while the sum is 31.

The square root of 228505261 is about 15116.3904752424. The cubic root of 228505261 is about 611.3624130443.

The spelling of 228505261 in words is "two hundred twenty-eight million, five hundred five thousand, two hundred sixty-one".