77868949 has 2 divisors, whose sum is σ = 77868950. Its totient is φ = 77868948.

The previous prime is 77868943. The next prime is 77868977. The reversal of 77868949 is 94986877.

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., 76562500 + 1306449 = 8750^2 + 1143^2 .

It is a cyclic number.

It is not a de Polignac number, because 77868949 - 2⁹ = 77868437 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 77868893 and 77868902.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77868943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38934474 + 38934475.

It is an arithmetic number, because the mean of its divisors is an integer number (38934475).

Almost surely, 2^77868949 is an apocalyptic number.

It is an amenable number.

77868949 is a deficient number, since it is larger than the sum of its proper divisors (1).

77868949 is an equidigital number, since it uses as much as digits as its factorization.

77868949 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6096384, while the sum is 58.

The square root of 77868949 is about 8824.3384454587. The cubic root of 77868949 is about 427.0264450602.

The spelling of 77868949 in words is "seventy-seven million, eight hundred sixty-eight thousand, nine hundred forty-nine".