61720849 has 2 divisors, whose sum is σ = 61720850. Its totient is φ = 61720848.

The previous prime is 61720801. The next prime is 61720859. The reversal of 61720849 is 94802716.

61720849 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57988225 + 3732624 = 7615^2 + 1932^2 .

It is a cyclic number.

It is not a de Polignac number, because 61720849 - 2¹¹ = 61718801 is a prime.

It is not a weakly prime, because it can be changed into another prime (61720859) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30860424 + 30860425.

It is an arithmetic number, because the mean of its divisors is an integer number (30860425).

Almost surely, 2^61720849 is an apocalyptic number.

It is an amenable number.

61720849 is a deficient number, since it is larger than the sum of its proper divisors (1).

61720849 is an equidigital number, since it uses as much as digits as its factorization.

61720849 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 61720849 is about 7856.2617700787. The cubic root of 61720849 is about 395.1942621874.

The spelling of 61720849 in words is "sixty-one million, seven hundred twenty thousand, eight hundred forty-nine".