228721129 has 32 divisors (see below), whose sum is σ = 293207040. Its totient is φ = 173601792.

The previous prime is 228721127. The next prime is 228721133. The reversal of 228721129 is 921127822.

It is not a de Polignac number, because 228721129 - 2¹ = 228721127 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 228721094 and 228721103.

It is not an unprimeable number, because it can be changed into a prime (228721121) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 226177 + ... + 227185.

It is an arithmetic number, because the mean of its divisors is an integer number (9162720).

Almost surely, 2^228721129 is an apocalyptic number.

It is an amenable number.

228721129 is a deficient number, since it is larger than the sum of its proper divisors (64485911).

228721129 is a wasteful number, since it uses less digits than its factorization.

228721129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1129.

The product of its digits is 8064, while the sum is 34.

The square root of 228721129 is about 15123.5289863180. The cubic root of 228721129 is about 611.5548696560.

The spelling of 228721129 in words is "two hundred twenty-eight million, seven hundred twenty-one thousand, one hundred twenty-nine".