28220337 has 6 divisors (see below), whose sum is σ = 40762722. Its totient is φ = 18813552.

The previous prime is 28220329. The next prime is 28220359. The reversal of 28220337 is 73302282.

It can be written as a sum of positive squares in only one way, i.e., 27499536 + 720801 = 5244^2 + 849^2 .

It is not a de Polignac number, because 28220337 - 2³ = 28220329 is a prime.

It is a super-4 number, since 4×28220337⁴ (a number of 31 digits) contains 4444 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28220337.

It is not an unprimeable number, because it can be changed into a prime (28220317) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1567788 + ... + 1567805.

It is an arithmetic number, because the mean of its divisors is an integer number (6793787).

Almost surely, 2^28220337 is an apocalyptic number.

It is an amenable number.

28220337 is a deficient number, since it is larger than the sum of its proper divisors (12542385).

28220337 is a wasteful number, since it uses less digits than its factorization.

28220337 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3135599 (or 3135596 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 27.

The square root of 28220337 is about 5312.2817131624. The cubic root of 28220337 is about 304.4533323289.

The spelling of 28220337 in words is "twenty-eight million, two hundred twenty thousand, three hundred thirty-seven".