228216861 has 6 divisors (see below), whose sum is σ = 329646590. Its totient is φ = 152144568.

The previous prime is 228216853. The next prime is 228216869. The reversal of 228216861 is 168612822.

It is an interprime number because it is at equal distance from previous prime (228216853) and next prime (228216869).

It can be written as a sum of positive squares in only one way, i.e., 158911236 + 69305625 = 12606^2 + 8325^2 .

It is not a de Polignac number, because 228216861 - 2³ = 228216853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (228216869) 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 5 ways as a sum of consecutive naturals, for example, 12678706 + ... + 12678723.

Almost surely, 2^228216861 is an apocalyptic number.

It is an amenable number.

228216861 is a deficient number, since it is larger than the sum of its proper divisors (101429729).

228216861 is a wasteful number, since it uses less digits than its factorization.

228216861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25357435 (or 25357432 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The square root of 228216861 is about 15106.8481491011. The cubic root of 228216861 is about 611.1051014640.

The spelling of 228216861 in words is "two hundred twenty-eight million, two hundred sixteen thousand, eight hundred sixty-one".