7821872 has 20 divisors (see below), whose sum is σ = 15508680. Its totient is φ = 3819648.

The previous prime is 7821859. The next prime is 7821893. The reversal of 7821872 is 2781287.

It is a super-2 number, since 2×7821872² = 122363363168768, which contains 22 as substring.

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4997 + ... + 6372.

It is an arithmetic number, because the mean of its divisors is an integer number (775434).

Almost surely, 2^7821872 is an apocalyptic number.

It is an amenable number.

7821872 is a deficient number, since it is larger than the sum of its proper divisors (7686808).

7821872 is a wasteful number, since it uses less digits than its factorization.

7821872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11420 (or 11414 counting only the distinct ones).

The product of its digits is 12544, while the sum is 35.

The square root of 7821872 is about 2796.7609837095. The cubic root of 7821872 is about 198.5044444436.

The spelling of 7821872 in words is "seven million, eight hundred twenty-one thousand, eight hundred seventy-two".