28305431406 has 24 divisors (see below), whose sum is σ = 70089639984. Its totient is φ = 8087266080.

The previous prime is 28305431389. The next prime is 28305431417. The reversal of 28305431406 is 60413450382.

It is a super-2 number, since 2×28305431406² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 112323015 + ... + 112323266.

It is an arithmetic number, because the mean of its divisors is an integer number (2920401666).

Almost surely, 2^28305431406 is an apocalyptic number.

28305431406 is an abundant number, since it is smaller than the sum of its proper divisors (41784208578).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28305431406 is a wasteful number, since it uses less digits than its factorization.

28305431406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224646296 (or 224646293 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

Adding to 28305431406 its reverse (60413450382), we get a palindrome (88718881788).

The spelling of 28305431406 in words is "twenty-eight billion, three hundred five million, four hundred thirty-one thousand, four hundred six".