28771613 has 4 divisors (see below), whose sum is σ = 30984828. Its totient is φ = 26558400.

The previous prime is 28771591. The next prime is 28771651. The reversal of 28771613 is 31617782.

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 17123044 + 11648569 = 4138^2 + 3413^2 .

It is a cyclic number.

It is not a de Polignac number, because 28771613 - 2⁶ = 28771549 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28771013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1106588 + ... + 1106613.

It is an arithmetic number, because the mean of its divisors is an integer number (7746207).

Almost surely, 2^28771613 is an apocalyptic number.

It is an amenable number.

28771613 is a deficient number, since it is larger than the sum of its proper divisors (2213215).

28771613 is a wasteful number, since it uses less digits than its factorization.

28771613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2213214.

The product of its digits is 14112, while the sum is 35.

The square root of 28771613 is about 5363.9176913894. The cubic root of 28771613 is about 306.4230304719.

The spelling of 28771613 in words is "twenty-eight million, seven hundred seventy-one thousand, six hundred thirteen".