7864 has 8 divisors (see below), whose sum is σ = 14760. Its totient is φ = 3928.

The previous prime is 7853. The next prime is 7867. The reversal of 7864 is 4687.

It is a tau number, because it is divible by the number of its divisors (8).

It is a plaindrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7867) by changing a digit.

7864 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 484 + ... + 499.

It is an arithmetic number, because the mean of its divisors is an integer number (1845).

2⁷⁸⁶⁴ is an apocalyptic number.

It is an amenable number.

7864 is a deficient number, since it is larger than the sum of its proper divisors (6896).

7864 is a wasteful number, since it uses less digits than its factorization.

7864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 989 (or 985 counting only the distinct ones).

The product of its digits is 1344, while the sum is 25.

The square root of 7864 is about 88.6791971096. The cubic root of 7864 is about 19.8860183094.

The spelling of 7864 in words is "seven thousand, eight hundred sixty-four".