61281716477 has 2 divisors, whose sum is σ = 61281716478. Its totient is φ = 61281716476.

The previous prime is 61281716407. The next prime is 61281716579. The reversal of 61281716477 is 77461718216.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60781478521 + 500237956 = 246539^2 + 22366^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61281716477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61281716407) 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, 30640858238 + 30640858239.

It is an arithmetic number, because the mean of its divisors is an integer number (30640858239).

Almost surely, 2^61281716477 is an apocalyptic number.

It is an amenable number.

61281716477 is a deficient number, since it is larger than the sum of its proper divisors (1).

61281716477 is an equidigital number, since it uses as much as digits as its factorization.

61281716477 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 790272, while the sum is 50.

The spelling of 61281716477 in words is "sixty-one billion, two hundred eighty-one million, seven hundred sixteen thousand, four hundred seventy-seven".