7821842 has 8 divisors (see below), whose sum is σ = 13408896. Its totient is φ = 3352212.

The previous prime is 7821841. The next prime is 7821859. The reversal of 7821842 is 2481287.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×7821842² = 122362424545928, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 7821799 and 7821808.

It is not an unprimeable number, because it can be changed into a prime (7821841) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 279338 + ... + 279365.

It is an arithmetic number, because the mean of its divisors is an integer number (1676112).

Almost surely, 2^7821842 is an apocalyptic number.

7821842 is a deficient number, since it is larger than the sum of its proper divisors (5587054).

7821842 is a wasteful number, since it uses less digits than its factorization.

7821842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 558712.

The product of its digits is 7168, while the sum is 32.

The square root of 7821842 is about 2796.7556203573. The cubic root of 7821842 is about 198.5041906621.

The spelling of 7821842 in words is "seven million, eight hundred twenty-one thousand, eight hundred forty-two".