28731361 has 2 divisors, whose sum is σ = 28731362. Its totient is φ = 28731360.

The previous prime is 28731359. The next prime is 28731371. The reversal of 28731361 is 16313782.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23464336 + 5267025 = 4844^2 + 2295^2 .

It is a cyclic number.

It is not a de Polignac number, because 28731361 - 2¹ = 28731359 is a prime.

It is a super-2 number, since 2×28731361² = 1650982209824642, which contains 22 as substring.

Together with 28731359, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (28731341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14365680 + 14365681.

It is an arithmetic number, because the mean of its divisors is an integer number (14365681).

Almost surely, 2^28731361 is an apocalyptic number.

It is an amenable number.

28731361 is a deficient number, since it is larger than the sum of its proper divisors (1).

28731361 is an equidigital number, since it uses as much as digits as its factorization.

28731361 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6048, while the sum is 31.

The square root of 28731361 is about 5360.1642698708. The cubic root of 28731361 is about 306.2800666857.

It can be divided in two parts, 28731 and 361, that added together give a palindrome (29092).

The spelling of 28731361 in words is "twenty-eight million, seven hundred thirty-one thousand, three hundred sixty-one".