77891369 has 4 divisors (see below), whose sum is σ = 78006096. Its totient is φ = 77776644.

The previous prime is 77891357. The next prime is 77891383. The reversal of 77891369 is 96319877.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 96319877 = 7247 ⋅13291.

It is a cyclic number.

It is not a de Polignac number, because 77891369 - 2⁸ = 77891113 is a prime.

It is a super-2 number, since 2×77891369² = 12134130729388322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77891309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56339 + ... + 57704.

It is an arithmetic number, because the mean of its divisors is an integer number (19501524).

Almost surely, 2^77891369 is an apocalyptic number.

It is an amenable number.

77891369 is a deficient number, since it is larger than the sum of its proper divisors (114727).

77891369 is a wasteful number, since it uses less digits than its factorization.

77891369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114726.

The product of its digits is 571536, while the sum is 50.

The square root of 77891369 is about 8825.6087042198. The cubic root of 77891369 is about 427.0674242281.

The spelling of 77891369 in words is "seventy-seven million, eight hundred ninety-one thousand, three hundred sixty-nine".