28399295381 has 4 divisors (see below), whose sum is σ = 29091961164. Its totient is φ = 27706629600.

The previous prime is 28399295341. The next prime is 28399295389. The reversal of 28399295381 is 18359299382.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5117113156 + 23282182225 = 71534^2 + 152585^2 .

It is a cyclic number.

It is not a de Polignac number, because 28399295381 - 2⁶ = 28399295317 is a prime.

It is a super-2 number, since 2×28399295381² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28399295381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28399295389) 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, 346332830 + ... + 346332911.

It is an arithmetic number, because the mean of its divisors is an integer number (7272990291).

Almost surely, 2^28399295381 is an apocalyptic number.

It is an amenable number.

28399295381 is a deficient number, since it is larger than the sum of its proper divisors (692665783).

28399295381 is an equidigital number, since it uses as much as digits as its factorization.

28399295381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 692665782.

The product of its digits is 8398080, while the sum is 59.

The spelling of 28399295381 in words is "twenty-eight billion, three hundred ninety-nine million, two hundred ninety-five thousand, three hundred eighty-one".