28644641993 has 8 divisors (see below), whose sum is σ = 31447738560. Its totient is φ = 25874718480.

The previous prime is 28644641957. The next prime is 28644642011. The reversal of 28644641993 is 39914644682.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28644641993 - 2³² = 24349674697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28644641903) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8291453 + ... + 8294906.

It is an arithmetic number, because the mean of its divisors is an integer number (3930967320).

Almost surely, 2^28644641993 is an apocalyptic number.

It is an amenable number.

28644641993 is a deficient number, since it is larger than the sum of its proper divisors (2803096567).

28644641993 is a wasteful number, since it uses less digits than its factorization.

28644641993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16586527.

The product of its digits is 8957952, while the sum is 56.

The spelling of 28644641993 in words is "twenty-eight billion, six hundred forty-four million, six hundred forty-one thousand, nine hundred ninety-three".