28737229 has 4 divisors (see below), whose sum is σ = 28759420. Its totient is φ = 28715040.

The previous prime is 28737223. The next prime is 28737239. The reversal of 28737229 is 92273782.

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

It can be written as a sum of positive squares in 2 ways, for example, as 10048900 + 18688329 = 3170^2 + 4323^2 .

It is a cyclic number.

It is not a de Polignac number, because 28737229 - 2¹⁹ = 28212941 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28737191 and 28737200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28737223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9024 + ... + 11785.

It is an arithmetic number, because the mean of its divisors is an integer number (7189855).

Almost surely, 2^28737229 is an apocalyptic number.

It is an amenable number.

28737229 is a deficient number, since it is larger than the sum of its proper divisors (22191).

28737229 is a wasteful number, since it uses less digits than its factorization.

28737229 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22190.

The product of its digits is 84672, while the sum is 40.

The square root of 28737229 is about 5360.7116132096. The cubic root of 28737229 is about 306.3009164822.

The spelling of 28737229 in words is "twenty-eight million, seven hundred thirty-seven thousand, two hundred twenty-nine".