7821265 has 12 divisors (see below), whose sum is σ = 9814644. Its totient is φ = 5982944.

The previous prime is 7821257. The next prime is 7821277. The reversal of 7821265 is 5621287.

It can be written as a sum of positive squares in 2 ways, for example, as 2099601 + 5721664 = 1449^2 + 2392^2 .

It is not a de Polignac number, because 7821265 - 2³ = 7821257 is a prime.

It is a super-2 number, since 2×7821265² = 122344372400450, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1167 + ... + 4123.

It is an arithmetic number, because the mean of its divisors is an integer number (817887).

Almost surely, 2^7821265 is an apocalyptic number.

It is an amenable number.

7821265 is a deficient number, since it is larger than the sum of its proper divisors (1993379).

7821265 is a wasteful number, since it uses less digits than its factorization.

7821265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3008 (or 2985 counting only the distinct ones).

The product of its digits is 6720, while the sum is 31.

The square root of 7821265 is about 2796.6524632138. The cubic root of 7821265 is about 198.4993094702.

The spelling of 7821265 in words is "seven million, eight hundred twenty-one thousand, two hundred sixty-five".