77997 has 4 divisors (see below), whose sum is σ = 104000. Its totient is φ = 51996.

The previous prime is 77983. The next prime is 77999. The reversal of 77997 is 79977.

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.

It is not a de Polignac number, because 77997 - 2⁶ = 77933 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77999) 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, 12997 + ... + 13002.

It is an arithmetic number, because the mean of its divisors is an integer number (26000).

2⁷⁷⁹⁹⁷ is an apocalyptic number.

It is an amenable number.

77997 is a deficient number, since it is larger than the sum of its proper divisors (26003).

77997 is a wasteful number, since it uses less digits than its factorization.

77997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26002.

The product of its digits is 27783, while the sum is 39.

The square root of 77997 is about 279.2794299622. The cubic root of 77997 is about 42.7260390332.

The spelling of 77997 in words is "seventy-seven thousand, nine hundred ninety-seven".