28707131 has 2 divisors, whose sum is σ = 28707132. Its totient is φ = 28707130.

The previous prime is 28707097. The next prime is 28707139. The reversal of 28707131 is 13170782.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28707131 - 2¹⁰ = 28706107 is a prime.

It is a super-2 number, since 2×28707131² = 1648198740502322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28707094 and 28707103.

It is not a weakly prime, because it can be changed into another prime (28707139) 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 as a sum of consecutive naturals, namely, 14353565 + 14353566.

It is an arithmetic number, because the mean of its divisors is an integer number (14353566).

Almost surely, 2^28707131 is an apocalyptic number.

28707131 is a deficient number, since it is larger than the sum of its proper divisors (1).

28707131 is an equidigital number, since it uses as much as digits as its factorization.

28707131 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2352, while the sum is 29.

The square root of 28707131 is about 5357.9036012232. The cubic root of 28707131 is about 306.1939441481.

It can be divided in two parts, 2870 and 7131, that added together give a palindrome (10001).

The spelling of 28707131 in words is "twenty-eight million, seven hundred seven thousand, one hundred thirty-one".