77891479 has 2 divisors, whose sum is σ = 77891480. Its totient is φ = 77891478.

The previous prime is 77891423. The next prime is 77891483. The reversal of 77891479 is 97419877.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 77891479 - 2⁷ = 77891351 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77898479) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38945739 + 38945740.

It is an arithmetic number, because the mean of its divisors is an integer number (38945740).

Almost surely, 2^77891479 is an apocalyptic number.

77891479 is a deficient number, since it is larger than the sum of its proper divisors (1).

77891479 is an equidigital number, since it uses as much as digits as its factorization.

77891479 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 889056, while the sum is 52.

The square root of 77891479 is about 8825.6149360824. The cubic root of 77891479 is about 427.0676252661.

The spelling of 77891479 in words is "seventy-seven million, eight hundred ninety-one thousand, four hundred seventy-nine".