28131313 has 8 divisors (see below), whose sum is σ = 32235840. Its totient is φ = 24048240.

The previous prime is 28131307. The next prime is 28131319. The reversal of 28131313 is 31313182.

It is an interprime number because it is at equal distance from previous prime (28131307) and next prime (28131319).

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28131313 is a prime.

It is a super-2 number, since 2×28131313² = 1582741542207938, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28131319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2443 + ... + 7888.

It is an arithmetic number, because the mean of its divisors is an integer number (4029480).

Almost surely, 2^28131313 is an apocalyptic number.

It is an amenable number.

28131313 is a deficient number, since it is larger than the sum of its proper divisors (4104527).

28131313 is a wasteful number, since it uses less digits than its factorization.

28131313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10727.

The product of its digits is 432, while the sum is 22.

The square root of 28131313 is about 5303.8960208511. The cubic root of 28131313 is about 304.1328518194.

Adding to 28131313 its reverse (31313182), we get a palindrome (59444495).

The spelling of 28131313 in words is "twenty-eight million, one hundred thirty-one thousand, three hundred thirteen".