77006804981 has 2 divisors, whose sum is σ = 77006804982. Its totient is φ = 77006804980.

The previous prime is 77006804893. The next prime is 77006805013. The reversal of 77006804981 is 18940860077.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46067753956 + 30939051025 = 214634^2 + 175895^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77006804981 is a prime.

It is a super-2 number, since 2×77006804981² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77006801981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38503402490 + 38503402491.

It is an arithmetic number, because the mean of its divisors is an integer number (38503402491).

Almost surely, 2^77006804981 is an apocalyptic number.

It is an amenable number.

77006804981 is a deficient number, since it is larger than the sum of its proper divisors (1).

77006804981 is an equidigital number, since it uses as much as digits as its factorization.

77006804981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 677376, while the sum is 50.

The spelling of 77006804981 in words is "seventy-seven billion, six million, eight hundred four thousand, nine hundred eighty-one".