28136531 has 2 divisors, whose sum is σ = 28136532. Its totient is φ = 28136530.

The previous prime is 28136489. The next prime is 28136551. The reversal of 28136531 is 13563182.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28136531 is a prime.

It is a super-2 number, since 2×28136531² = 1583328753427922, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 28136494 and 28136503.

It is not a weakly prime, because it can be changed into another prime (28136551) 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, 14068265 + 14068266.

It is an arithmetic number, because the mean of its divisors is an integer number (14068266).

Almost surely, 2^28136531 is an apocalyptic number.

28136531 is a deficient number, since it is larger than the sum of its proper divisors (1).

28136531 is an equidigital number, since it uses as much as digits as its factorization.

28136531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4320, while the sum is 29.

The square root of 28136531 is about 5304.3879005970. The cubic root of 28136531 is about 304.1516549127.

The spelling of 28136531 in words is "twenty-eight million, one hundred thirty-six thousand, five hundred thirty-one".