869820449 has 4 divisors (see below), whose sum is σ = 869936964. Its totient is φ = 869703936.

The previous prime is 869820433. The next prime is 869820451. The reversal of 869820449 is 944028968.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 736579600 + 133240849 = 27140^2 + 11543^2 .

It is a cyclic number.

It is not a de Polignac number, because 869820449 - 2⁴ = 869820433 is a prime.

It is a super-2 number, since 2×869820449² = 1513175226997123202, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 869820397 and 869820406.

It is not an unprimeable number, because it can be changed into a prime (869820409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46232 + ... + 62265.

It is an arithmetic number, because the mean of its divisors is an integer number (217484241).

Almost surely, 2^869820449 is an apocalyptic number.

It is an amenable number.

869820449 is a deficient number, since it is larger than the sum of its proper divisors (116515).

869820449 is a wasteful number, since it uses less digits than its factorization.

869820449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116514.

The product of its (nonzero) digits is 995328, while the sum is 50.

The square root of 869820449 is about 29492.7185759468. The cubic root of 869820449 is about 954.5745933849.

The spelling of 869820449 in words is "eight hundred sixty-nine million, eight hundred twenty thousand, four hundred forty-nine".