28216069 has 4 divisors (see below), whose sum is σ = 32246944. Its totient is φ = 24185196.

The previous prime is 28216049. The next prime is 28216079. The reversal of 28216069 is 96061282.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 28216069 - 2⁵ = 28216037 is a prime.

It is a super-2 number, since 2×28216069² = 1592293099625522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28216049) 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, 2015427 + ... + 2015440.

It is an arithmetic number, because the mean of its divisors is an integer number (8061736).

Almost surely, 2^28216069 is an apocalyptic number.

It is an amenable number.

28216069 is a deficient number, since it is larger than the sum of its proper divisors (4030875).

28216069 is an equidigital number, since it uses as much as digits as its factorization.

28216069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4030874.

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 28216069 is about 5311.8799873491. The cubic root of 28216069 is about 304.4379832052.

The spelling of 28216069 in words is "twenty-eight million, two hundred sixteen thousand, sixty-nine".