61777473217 has 2 divisors, whose sum is σ = 61777473218. Its totient is φ = 61777473216.

The previous prime is 61777473137. The next prime is 61777473229. The reversal of 61777473217 is 71237477716.

61777473217 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., 37513491856 + 24263981361 = 193684^2 + 155769^2 .

It is a cyclic number.

It is not a de Polignac number, because 61777473217 - 2¹⁵ = 61777440449 is a prime.

It is not a weakly prime, because it can be changed into another prime (61777473817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30888736608 + 30888736609.

It is an arithmetic number, because the mean of its divisors is an integer number (30888736609).

Almost surely, 2^61777473217 is an apocalyptic number.

It is an amenable number.

61777473217 is a deficient number, since it is larger than the sum of its proper divisors (1).

61777473217 is an equidigital number, since it uses as much as digits as its factorization.

61777473217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2420208, while the sum is 52.

The spelling of 61777473217 in words is "sixty-one billion, seven hundred seventy-seven million, four hundred seventy-three thousand, two hundred seventeen".