228521139 has 32 divisors (see below), whose sum is σ = 390160896. Its totient is φ = 115499520.

The previous prime is 228521129. The next prime is 228521159. The reversal of 228521139 is 931125822.

It is a happy number.

It is not a de Polignac number, because 228521139 - 2²⁷ = 94303411 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (228521129) 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, 4822 + ... + 21915.

It is an arithmetic number, because the mean of its divisors is an integer number (12192528).

Almost surely, 2^228521139 is an apocalyptic number.

228521139 is a deficient number, since it is larger than the sum of its proper divisors (161639757).

228521139 is a wasteful number, since it uses less digits than its factorization.

228521139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26795.

The product of its digits is 8640, while the sum is 33.

The square root of 228521139 is about 15116.9156576333. The cubic root of 228521139 is about 611.3765731669.

The spelling of 228521139 in words is "two hundred twenty-eight million, five hundred twenty-one thousand, one hundred thirty-nine".