77125691 has 2 divisors, whose sum is σ = 77125692. Its totient is φ = 77125690.

The previous prime is 77125687. The next prime is 77125717. The reversal of 77125691 is 19652177.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 77125691 - 2² = 77125687 is a prime.

It is not a weakly prime, because it can be changed into another prime (77125681) 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, 38562845 + 38562846.

It is an arithmetic number, because the mean of its divisors is an integer number (38562846).

Almost surely, 2^77125691 is an apocalyptic number.

77125691 is a deficient number, since it is larger than the sum of its proper divisors (1).

77125691 is an equidigital number, since it uses as much as digits as its factorization.

77125691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 26460, while the sum is 38.

The square root of 77125691 is about 8782.1233764961. The cubic root of 77125691 is about 425.6634454517.

It can be divided in two parts, 771 and 25691, that added together give a palindrome (26462).

The spelling of 77125691 in words is "seventy-seven million, one hundred twenty-five thousand, six hundred ninety-one".