7821396 has 36 divisors (see below), whose sum is σ = 21569184. Its totient is φ = 2370000.

The previous prime is 7821383. The next prime is 7821397. The reversal of 7821396 is 6931287.

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

It is a super-2 number, since 2×7821396² = 122348470777632, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 7821396.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7821397) 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, 9480 + ... + 10271.

It is an arithmetic number, because the mean of its divisors is an integer number (599144).

Almost surely, 2^7821396 is an apocalyptic number.

It is an amenable number.

7821396 is an abundant number, since it is smaller than the sum of its proper divisors (13747788).

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

7821396 is a wasteful number, since it uses less digits than its factorization.

7821396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19772 (or 19767 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 7821396 is about 2796.6758839737. The cubic root of 7821396 is about 198.5004176995.

The spelling of 7821396 in words is "seven million, eight hundred twenty-one thousand, three hundred ninety-six".