77897 has 4 divisors (see below), whose sum is σ = 79236. Its totient is φ = 76560.

The previous prime is 77893. The next prime is 77899. The reversal of 77897 is 79877.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 79877 = 7 ⋅11411.

It can be written as a sum of positive squares in 2 ways, for example, as 22201 + 55696 = 149^2 + 236^2 .

It is a cyclic number.

It is not a de Polignac number, because 77897 - 2² = 77893 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 77897.

It is not an unprimeable number, because it can be changed into a prime (77893) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 578 + ... + 699.

It is an arithmetic number, because the mean of its divisors is an integer number (19809).

2⁷⁷⁸⁹⁷ is an apocalyptic number.

It is an amenable number.

77897 is a deficient number, since it is larger than the sum of its proper divisors (1339).

77897 is a wasteful number, since it uses less digits than its factorization.

77897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1338.

The product of its digits is 24696, while the sum is 38.

The square root of 77897 is about 279.1003403796. The cubic root of 77897 is about 42.7077715307.

It can be divided in two parts, 778 and 97, that multiplied together give a triangular number (75466 = T₃₈₈).

The spelling of 77897 in words is "seventy-seven thousand, eight hundred ninety-seven".