8021749 has 2 divisors, whose sum is σ = 8021750. Its totient is φ = 8021748.

The previous prime is 8021747. The next prime is 8021753. The reversal of 8021749 is 9471208.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7800849 + 220900 = 2793^2 + 470^2 .

It is a cyclic number.

It is not a de Polignac number, because 8021749 - 2¹ = 8021747 is a prime.

Together with 8021747, it forms a pair of twin primes.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 8021749.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8021747) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4010874 + 4010875.

It is an arithmetic number, because the mean of its divisors is an integer number (4010875).

Almost surely, 2^8021749 is an apocalyptic number.

It is an amenable number.

8021749 is a deficient number, since it is larger than the sum of its proper divisors (1).

8021749 is an equidigital number, since it uses as much as digits as its factorization.

8021749 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 8021749 is about 2832.2692315527. The cubic root of 8021749 is about 200.1810776716.

The spelling of 8021749 in words is "eight million, twenty-one thousand, seven hundred forty-nine".