77381 has 4 divisors (see below), whose sum is σ = 77952. Its totient is φ = 76812.

The previous prime is 77377. The next prime is 77383. The reversal of 77381 is 18377.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 77381 - 2² = 77377 is a prime.

It is a super-2 number, since 2×77381² = 11975638322, which contains 22 as substring.

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 77381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77383) 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, 50 + ... + 396.

It is an arithmetic number, because the mean of its divisors is an integer number (19488).

2⁷⁷³⁸¹ is an apocalyptic number.

It is an amenable number.

77381 is a deficient number, since it is larger than the sum of its proper divisors (571).

77381 is a wasteful number, since it uses less digits than its factorization.

77381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 570.

The product of its digits is 1176, while the sum is 26.

The square root of 77381 is about 278.1744057242. The cubic root of 77381 is about 42.6132619043.

The spelling of 77381 in words is "seventy-seven thousand, three hundred eighty-one".