228721139 has 2 divisors, whose sum is σ = 228721140. Its totient is φ = 228721138.

The previous prime is 228721133. The next prime is 228721151. The reversal of 228721139 is 931127822.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 228721139 - 2⁴ = 228721123 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 228721099 and 228721108.

It is not a weakly prime, because it can be changed into another prime (228721133) 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 as a sum of consecutive naturals, namely, 114360569 + 114360570.

It is an arithmetic number, because the mean of its divisors is an integer number (114360570).

Almost surely, 2^228721139 is an apocalyptic number.

228721139 is a deficient number, since it is larger than the sum of its proper divisors (1).

228721139 is an equidigital number, since it uses as much as digits as its factorization.

228721139 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 35.

The square root of 228721139 is about 15123.5293169286. The cubic root of 228721139 is about 611.5548785686.

The spelling of 228721139 in words is "two hundred twenty-eight million, seven hundred twenty-one thousand, one hundred thirty-nine".