77685137 has 2 divisors, whose sum is σ = 77685138. Its totient is φ = 77685136.

The previous prime is 77685079. The next prime is 77685151. The reversal of 77685137 is 73158677.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 67502656 + 10182481 = 8216^2 + 3191^2 .

It is a cyclic number.

It is not a de Polignac number, because 77685137 - 2¹⁴ = 77668753 is a prime.

It is not a weakly prime, because it can be changed into another prime (77685187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38842568 + 38842569.

It is an arithmetic number, because the mean of its divisors is an integer number (38842569).

Almost surely, 2^77685137 is an apocalyptic number.

It is an amenable number.

77685137 is a deficient number, since it is larger than the sum of its proper divisors (1).

77685137 is an equidigital number, since it uses as much as digits as its factorization.

77685137 is an evil number, because the sum of its binary digits is even.

The product of its digits is 246960, while the sum is 44.

The square root of 77685137 is about 8813.9172335574. The cubic root of 77685137 is about 426.6901774018.

The spelling of 77685137 in words is "seventy-seven million, six hundred eighty-five thousand, one hundred thirty-seven".