77668289 has 2 divisors, whose sum is σ = 77668290. Its totient is φ = 77668288.

The previous prime is 77668273. The next prime is 77668303. The reversal of 77668289 is 98286677.

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., 56370064 + 21298225 = 7508^2 + 4615^2 .

It is a cyclic number.

It is not a de Polignac number, because 77668289 - 2⁴ = 77668273 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 77668289.

It is not a weakly prime, because it can be changed into another prime (77668229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38834144 + 38834145.

It is an arithmetic number, because the mean of its divisors is an integer number (38834145).

Almost surely, 2^77668289 is an apocalyptic number.

It is an amenable number.

77668289 is a deficient number, since it is larger than the sum of its proper divisors (1).

77668289 is an equidigital number, since it uses as much as digits as its factorization.

77668289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2032128, while the sum is 53.

The square root of 77668289 is about 8812.9614205442. The cubic root of 77668289 is about 426.6593289618.

The spelling of 77668289 in words is "seventy-seven million, six hundred sixty-eight thousand, two hundred eighty-nine".