28140949 has 2 divisors, whose sum is σ = 28140950. Its totient is φ = 28140948.

The previous prime is 28140943. The next prime is 28140971. The reversal of 28140949 is 94904182.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20340100 + 7800849 = 4510^2 + 2793^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28140949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28140943) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14070474 + 14070475.

It is an arithmetic number, because the mean of its divisors is an integer number (14070475).

Almost surely, 2^28140949 is an apocalyptic number.

It is an amenable number.

28140949 is a deficient number, since it is larger than the sum of its proper divisors (1).

28140949 is an equidigital number, since it uses as much as digits as its factorization.

28140949 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 28140949 is about 5304.8043319240. The cubic root of 28140949 is about 304.1675733840.

The spelling of 28140949 in words is "twenty-eight million, one hundred forty thousand, nine hundred forty-nine".