28944421869 has 16 divisors (see below), whose sum is σ = 43127832384. Its totient is φ = 17114217600.

The previous prime is 28944421853. The next prime is 28944421871. The reversal of 28944421869 is 96812444982.

It is a happy number.

It is not a de Polignac number, because 28944421869 - 2⁴ = 28944421853 is a prime.

It is a super-2 number, since 2×28944421869² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28944421069) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10695034 + ... + 10697739.

It is an arithmetic number, because the mean of its divisors is an integer number (2695489524).

Almost surely, 2^28944421869 is an apocalyptic number.

It is an amenable number.

28944421869 is a deficient number, since it is larger than the sum of its proper divisors (14183410515).

28944421869 is a wasteful number, since it uses less digits than its factorization.

28944421869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21392828.

The product of its digits is 7962624, while the sum is 57.

The spelling of 28944421869 in words is "twenty-eight billion, nine hundred forty-four million, four hundred twenty-one thousand, eight hundred sixty-nine".