28307491 has 2 divisors, whose sum is σ = 28307492. Its totient is φ = 28307490.

The previous prime is 28307483. The next prime is 28307501. The reversal of 28307491 is 19470382.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28307491 - 2³ = 28307483 is a prime.

It is not a weakly prime, because it can be changed into another prime (28307441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14153745 + 14153746.

It is an arithmetic number, because the mean of its divisors is an integer number (14153746).

Almost surely, 2^28307491 is an apocalyptic number.

28307491 is a deficient number, since it is larger than the sum of its proper divisors (1).

28307491 is an equidigital number, since it uses as much as digits as its factorization.

28307491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 28307491 is about 5320.4784559286. The cubic root of 28307491 is about 304.7664287178.

The spelling of 28307491 in words is "twenty-eight million, three hundred seven thousand, four hundred ninety-one".