61564646513 has 2 divisors, whose sum is σ = 61564646514. Its totient is φ = 61564646512.

The previous prime is 61564646497. The next prime is 61564646519. The reversal of 61564646513 is 31564646516.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57531380449 + 4033266064 = 239857^2 + 63508^2 .

It is a cyclic number.

It is not a de Polignac number, because 61564646513 - 2⁴ = 61564646497 is a prime.

It is not a weakly prime, because it can be changed into another prime (61564646519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30782323256 + 30782323257.

It is an arithmetic number, because the mean of its divisors is an integer number (30782323257).

Almost surely, 2^61564646513 is an apocalyptic number.

It is an amenable number.

61564646513 is a deficient number, since it is larger than the sum of its proper divisors (1).

61564646513 is an equidigital number, since it uses as much as digits as its factorization.

61564646513 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1555200, while the sum is 47.

The spelling of 61564646513 in words is "sixty-one billion, five hundred sixty-four million, six hundred forty-six thousand, five hundred thirteen".