1395821 has 4 divisors (see below), whose sum is σ = 1595232. Its totient is φ = 1196412.

The previous prime is 1395817. The next prime is 1395829. The reversal of 1395821 is 1285931.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1395821 - 2² = 1395817 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1395829) 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 3 ways as a sum of consecutive naturals, for example, 99695 + ... + 99708.

It is an arithmetic number, because the mean of its divisors is an integer number (398808).

2^1395821 is an apocalyptic number.

It is an amenable number.

1395821 is a deficient number, since it is larger than the sum of its proper divisors (199411).

1395821 is an equidigital number, since it uses as much as digits as its factorization.

1395821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199410.

The product of its digits is 2160, while the sum is 29.

The square root of 1395821 is about 1181.4486869941. The cubic root of 1395821 is about 111.7574737214.

The spelling of 1395821 in words is "one million, three hundred ninety-five thousand, eight hundred twenty-one".