821364669 has 12 divisors (see below), whose sum is σ = 1198647996. Its totient is φ = 541930752.

The previous prime is 821364667. The next prime is 821364671. The reversal of 821364669 is 966463128.

It is an interprime number because it is at equal distance from previous prime (821364667) and next prime (821364671).

It can be written as a sum of positive squares in 2 ways, for example, as 500059044 + 321305625 = 22362^2 + 17925^2 .

It is not a de Polignac number, because 821364669 - 2¹ = 821364667 is a prime.

It is a super-3 number, since 3×821364669³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821364667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 469554 + ... + 471299.

It is an arithmetic number, because the mean of its divisors is an integer number (99887333).

Almost surely, 2^821364669 is an apocalyptic number.

It is an amenable number.

821364669 is a deficient number, since it is larger than the sum of its proper divisors (377283327).

821364669 is a wasteful number, since it uses less digits than its factorization.

821364669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 940956 (or 940953 counting only the distinct ones).

The product of its digits is 373248, while the sum is 45.

The square root of 821364669 is about 28659.4603752408. The cubic root of 821364669 is about 936.5091089930.

The spelling of 821364669 in words is "eight hundred twenty-one million, three hundred sixty-four thousand, six hundred sixty-nine".