228406639 has 4 divisors (see below), whose sum is σ = 236282760. Its totient is φ = 220530520.

The previous prime is 228406637. The next prime is 228406693. The reversal of 228406639 is 936604822.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 228406639 - 2¹ = 228406637 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 (228406637) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3938017 + ... + 3938074.

It is an arithmetic number, because the mean of its divisors is an integer number (59070690).

Almost surely, 2^228406639 is an apocalyptic number.

228406639 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

228406639 is a deficient number, since it is larger than the sum of its proper divisors (7876121).

228406639 is an equidigital number, since it uses as much as digits as its factorization.

228406639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7876120.

The product of its (nonzero) digits is 124416, while the sum is 40.

The square root of 228406639 is about 15113.1280349238. The cubic root of 228406639 is about 611.2744464917.

The spelling of 228406639 in words is "two hundred twenty-eight million, four hundred six thousand, six hundred thirty-nine".