77344615861 has 2 divisors, whose sum is σ = 77344615862. Its totient is φ = 77344615860.

The previous prime is 77344615847. The next prime is 77344615891. The reversal of 77344615861 is 16851644377.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 45978080625 + 31366535236 = 214425^2 + 177106^2 .

It is a cyclic number.

It is not a de Polignac number, because 77344615861 - 2¹⁵ = 77344583093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 77344615799 and 77344615808.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77344615801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38672307930 + 38672307931.

It is an arithmetic number, because the mean of its divisors is an integer number (38672307931).

Almost surely, 2^77344615861 is an apocalyptic number.

It is an amenable number.

77344615861 is a deficient number, since it is larger than the sum of its proper divisors (1).

77344615861 is an equidigital number, since it uses as much as digits as its factorization.

77344615861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3386880, while the sum is 52.

The spelling of 77344615861 in words is "seventy-seven billion, three hundred forty-four million, six hundred fifteen thousand, eight hundred sixty-one".