28201993 has 2 divisors, whose sum is σ = 28201994. Its totient is φ = 28201992.

The previous prime is 28201969. The next prime is 28202011. The reversal of 28201993 is 39910282.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15155449 + 13046544 = 3893^2 + 3612^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28201993 is a prime.

It is not a weakly prime, because it can be changed into another prime (28201903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14100996 + 14100997.

It is an arithmetic number, because the mean of its divisors is an integer number (14100997).

Almost surely, 2^28201993 is an apocalyptic number.

It is an amenable number.

28201993 is a deficient number, since it is larger than the sum of its proper divisors (1).

28201993 is an equidigital number, since it uses as much as digits as its factorization.

28201993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 28201993 is about 5310.5548674315. The cubic root of 28201993 is about 304.3873503331.

The spelling of 28201993 in words is "twenty-eight million, two hundred one thousand, nine hundred ninety-three".