7812 has 36 divisors (see below), whose sum is σ = 23296. Its totient is φ = 2160.

The previous prime is 7793. The next prime is 7817. The reversal of 7812 is 2187.

7812 is nontrivially palindromic in base 5.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×7812² = 122054688, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an alternating number because its digits alternate between odd and even.

7812 is a nontrivial repdigit in base 5.

It is a plaindrome in base 5 and base 15.

It is a nialpdrome in base 5.

It is a zygodrome in base 5.

It is not an unprimeable number, because it can be changed into a prime (7817) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 237 + ... + 267.

2⁷⁸¹² is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7812, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11648).

7812 is an abundant number, since it is smaller than the sum of its proper divisors (15484).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7812 is a wasteful number, since it uses less digits than its factorization.

7812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48 (or 43 counting only the distinct ones).

The product of its digits is 112, while the sum is 18.

The square root of 7812 is about 88.3855191759. The cubic root of 7812 is about 19.8420898336.

7812 divided by its sum of digits (18) gives a palindrome (434).

Adding to 7812 its reverse (2187), we get a palindrome (9999).

Subtracting from 7812 its reverse (2187), we obtain a square (5625 = 75²).

The spelling of 7812 in words is "seven thousand, eight hundred twelve".