8121749 has 2 divisors, whose sum is σ = 8121750. Its totient is φ = 8121748.

The previous prime is 8121739. The next prime is 8121793. The reversal of 8121749 is 9471218.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7941124 + 180625 = 2818^2 + 425^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8121749 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8121709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4060874 + 4060875.

It is an arithmetic number, because the mean of its divisors is an integer number (4060875).

Almost surely, 2^8121749 is an apocalyptic number.

It is an amenable number.

8121749 is a deficient number, since it is larger than the sum of its proper divisors (1).

8121749 is an equidigital number, since it uses as much as digits as its factorization.

8121749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4032, while the sum is 32.

The square root of 8121749 is about 2849.8682425684. The cubic root of 8121749 is about 201.0094712664.

The spelling of 8121749 in words is "eight million, one hundred twenty-one thousand, seven hundred forty-nine".