77280977 has 2 divisors, whose sum is σ = 77280978. Its totient is φ = 77280976.

The previous prime is 77280953. The next prime is 77280991. The reversal of 77280977 is 77908277.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63856081 + 13424896 = 7991^2 + 3664^2 .

It is a cyclic number.

It is not a de Polignac number, because 77280977 - 2⁶ = 77280913 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (77280937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38640488 + 38640489.

It is an arithmetic number, because the mean of its divisors is an integer number (38640489).

Almost surely, 2^77280977 is an apocalyptic number.

It is an amenable number.

77280977 is a deficient number, since it is larger than the sum of its proper divisors (1).

77280977 is an equidigital number, since it uses as much as digits as its factorization.

77280977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 345744, while the sum is 47.

The square root of 77280977 is about 8790.9599589578. The cubic root of 77280977 is about 425.9489329485.

The spelling of 77280977 in words is "seventy-seven million, two hundred eighty thousand, nine hundred seventy-seven".