428308949 has 2 divisors, whose sum is σ = 428308950. Its totient is φ = 428308948.

The previous prime is 428308879. The next prime is 428308973. The reversal of 428308949 is 949803824.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 408444100 + 19864849 = 20210^2 + 4457^2 .

It is a cyclic number.

It is not a de Polignac number, because 428308949 - 2¹² = 428304853 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (428308249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 214154474 + 214154475.

It is an arithmetic number, because the mean of its divisors is an integer number (214154475).

Almost surely, 2^428308949 is an apocalyptic number.

It is an amenable number.

428308949 is a deficient number, since it is larger than the sum of its proper divisors (1).

428308949 is an equidigital number, since it uses as much as digits as its factorization.

428308949 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 497664, while the sum is 47.

The square root of 428308949 is about 20695.6263253858. The cubic root of 428308949 is about 753.7934907393.

The spelling of 428308949 in words is "four hundred twenty-eight million, three hundred eight thousand, nine hundred forty-nine".