28666069 has 4 divisors (see below), whose sum is σ = 28689696. Its totient is φ = 28642444.

The previous prime is 28666031. The next prime is 28666081. The reversal of 28666069 is 96066682.

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 a cyclic number.

It is not a de Polignac number, because 28666069 - 2¹⁷ = 28534997 is a prime.

It is a super-2 number, since 2×28666069² = 1643487023825522, 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 (28666769) 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, 9889 + ... + 12454.

It is an arithmetic number, because the mean of its divisors is an integer number (7172424).

Almost surely, 2^28666069 is an apocalyptic number.

It is an amenable number.

28666069 is a deficient number, since it is larger than the sum of its proper divisors (23627).

28666069 is a wasteful number, since it uses less digits than its factorization.

28666069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23626.

The product of its (nonzero) digits is 186624, while the sum is 43.

The square root of 28666069 is about 5354.0703207933. The cubic root of 28666069 is about 306.0478836312.

The spelling of 28666069 in words is "twenty-eight million, six hundred sixty-six thousand, sixty-nine".