8420749 has 2 divisors, whose sum is σ = 8420750. Its totient is φ = 8420748.

The previous prime is 8420681. The next prime is 8420771. The reversal of 8420749 is 9470248.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4380649 + 4040100 = 2093^2 + 2010^2 .

It is a cyclic number.

It is not a de Polignac number, because 8420749 - 2²³ = 32141 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8420149) 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, 4210374 + 4210375.

It is an arithmetic number, because the mean of its divisors is an integer number (4210375).

Almost surely, 2^8420749 is an apocalyptic number.

It is an amenable number.

8420749 is a deficient number, since it is larger than the sum of its proper divisors (1).

8420749 is an equidigital number, since it uses as much as digits as its factorization.

8420749 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 8420749 is about 2901.8526840624. The cubic root of 8420749 is about 203.4465084067.

The spelling of 8420749 in words is "eight million, four hundred twenty thousand, seven hundred forty-nine".