28943693 has 4 divisors (see below), whose sum is σ = 29019648. Its totient is φ = 28867740.

The previous prime is 28943659. The next prime is 28943699. The reversal of 28943693 is 39634982.

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 a de Polignac number, because none of the positive numbers 2^k-28943693 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28943699) 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, 37403 + ... + 38168.

It is an arithmetic number, because the mean of its divisors is an integer number (7254912).

Almost surely, 2^28943693 is an apocalyptic number.

It is an amenable number.

28943693 is a deficient number, since it is larger than the sum of its proper divisors (75955).

28943693 is an equidigital number, since it uses as much as digits as its factorization.

28943693 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75954.

The product of its digits is 279936, while the sum is 44.

The square root of 28943693 is about 5379.9342932791. The cubic root of 28943693 is about 307.0327112736.

The spelling of 28943693 in words is "twenty-eight million, nine hundred forty-three thousand, six hundred ninety-three".