821149 has 4 divisors (see below), whose sum is σ = 938464. Its totient is φ = 703836.

The previous prime is 821147. The next prime is 821153. The reversal of 821149 is 941128.

It is a happy number.

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 821149 - 2¹ = 821147 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 (821143) 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, 58647 + ... + 58660.

It is an arithmetic number, because the mean of its divisors is an integer number (234616).

2⁸²¹¹⁴⁹ is an apocalyptic number.

It is an amenable number.

821149 is a deficient number, since it is larger than the sum of its proper divisors (117315).

821149 is a wasteful number, since it uses less digits than its factorization.

821149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117314.

The product of its digits is 576, while the sum is 25.

The square root of 821149 is about 906.1727208430. The cubic root of 821149 is about 93.6427134173.

The spelling of 821149 in words is "eight hundred twenty-one thousand, one hundred forty-nine".