77764481 has 2 divisors, whose sum is σ = 77764482. Its totient is φ = 77764480.

The previous prime is 77764459. The next prime is 77764493. The reversal of 77764481 is 18446777.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74666881 + 3097600 = 8641^2 + 1760^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77764481 is a prime.

It is a super-2 number, since 2×77764481² = 12094629010398722, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (77764781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38882240 + 38882241.

It is an arithmetic number, because the mean of its divisors is an integer number (38882241).

Almost surely, 2^77764481 is an apocalyptic number.

It is an amenable number.

77764481 is a deficient number, since it is larger than the sum of its proper divisors (1).

77764481 is an equidigital number, since it uses as much as digits as its factorization.

77764481 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 263424, while the sum is 44.

The square root of 77764481 is about 8818.4171482188. The cubic root of 77764481 is about 426.8353951668.

The spelling of 77764481 in words is "seventy-seven million, seven hundred sixty-four thousand, four hundred eighty-one".