7821441 has 14 divisors (see below), whose sum is σ = 11727890. Its totient is φ = 5213808.

The previous prime is 7821427. The next prime is 7821461. The reversal of 7821441 is 1441287.

It can be written as a sum of positive squares in only one way, i.e., 7290000 + 531441 = 2700^2 + 729^2 .

It is not a de Polignac number, because 7821441 - 2⁹ = 7820929 is a prime.

It is a super-2 number, since 2×7821441² = 122349878632962, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (7821461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 4636 + ... + 6093.

Almost surely, 2^7821441 is an apocalyptic number.

It is an amenable number.

7821441 is a deficient number, since it is larger than the sum of its proper divisors (3906449).

7821441 is an equidigital number, since it uses as much as digits as its factorization.

7821441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10747 (or 10732 counting only the distinct ones).

The product of its digits is 1792, while the sum is 27.

The square root of 7821441 is about 2796.6839292276. The cubic root of 7821441 is about 198.5007983861.

The spelling of 7821441 in words is "seven million, eight hundred twenty-one thousand, four hundred forty-one".