77828549 has 2 divisors, whose sum is σ = 77828550. Its totient is φ = 77828548.

The previous prime is 77828461. The next prime is 77828591. The reversal of 77828549 is 94582877.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43230625 + 34597924 = 6575^2 + 5882^2 .

It is a cyclic number.

It is not a de Polignac number, because 77828549 - 2¹⁶ = 77763013 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 77828497 and 77828506.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77828599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38914274 + 38914275.

It is an arithmetic number, because the mean of its divisors is an integer number (38914275).

Almost surely, 2^77828549 is an apocalyptic number.

It is an amenable number.

77828549 is a deficient number, since it is larger than the sum of its proper divisors (1).

77828549 is an equidigital number, since it uses as much as digits as its factorization.

77828549 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1128960, while the sum is 50.

The square root of 77828549 is about 8822.0490250281. The cubic root of 77828549 is about 426.9525822732.

The spelling of 77828549 in words is "seventy-seven million, eight hundred twenty-eight thousand, five hundred forty-nine".