77991041 has 2 divisors, whose sum is σ = 77991042. Its totient is φ = 77991040.

The previous prime is 77991031. The next prime is 77991049. The reversal of 77991041 is 14019977.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 76195441 + 1795600 = 8729^2 + 1340^2 .

It is an emirp because it is prime and its reverse (14019977) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77991041 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 77990986 and 77991004.

It is not a weakly prime, because it can be changed into another prime (77991049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38995520 + 38995521.

It is an arithmetic number, because the mean of its divisors is an integer number (38995521).

Almost surely, 2^77991041 is an apocalyptic number.

It is an amenable number.

77991041 is a deficient number, since it is larger than the sum of its proper divisors (1).

77991041 is an equidigital number, since it uses as much as digits as its factorization.

77991041 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15876, while the sum is 38.

The square root of 77991041 is about 8831.2536482653. The cubic root of 77991041 is about 427.2495091036.

The spelling of 77991041 in words is "seventy-seven million, nine hundred ninety-one thousand, forty-one".