28281971 has 2 divisors, whose sum is σ = 28281972. Its totient is φ = 28281970.

The previous prime is 28281907. The next prime is 28281991. The reversal of 28281971 is 17918282.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28281971 - 2⁶ = 28281907 is a prime.

It is not a weakly prime, because it can be changed into another prime (28281901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14140985 + 14140986.

It is an arithmetic number, because the mean of its divisors is an integer number (14140986).

Almost surely, 2^28281971 is an apocalyptic number.

28281971 is a deficient number, since it is larger than the sum of its proper divisors (1).

28281971 is an equidigital number, since it uses as much as digits as its factorization.

28281971 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16128, while the sum is 38.

The square root of 28281971 is about 5318.0796346050. The cubic root of 28281971 is about 304.6748160102.

The spelling of 28281971 in words is "twenty-eight million, two hundred eighty-one thousand, nine hundred seventy-one".