28723207 has 2 divisors, whose sum is σ = 28723208. Its totient is φ = 28723206.

The previous prime is 28723199. The next prime is 28723249. The reversal of 28723207 is 70232782.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28723207 - 2³ = 28723199 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28723007) 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, 14361603 + 14361604.

It is an arithmetic number, because the mean of its divisors is an integer number (14361604).

Almost surely, 2^28723207 is an apocalyptic number.

28723207 is a deficient number, since it is larger than the sum of its proper divisors (1).

28723207 is an equidigital number, since it uses as much as digits as its factorization.

28723207 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9408, while the sum is 31.

The square root of 28723207 is about 5359.4036048799. The cubic root of 28723207 is about 306.2510897087.

Adding to 28723207 its reverse (70232782), we get a palindrome (98955989).

The spelling of 28723207 in words is "twenty-eight million, seven hundred twenty-three thousand, two hundred seven".