844140820 has 12 divisors (see below), whose sum is σ = 1772695764. Its totient is φ = 337656320.

The previous prime is 844140811. The next prime is 844140827. The reversal of 844140820 is 28041448.

It can be written as a sum of positive squares in 2 ways, for example, as 665330436 + 178810384 = 25794^2 + 13372^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (844140827) 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, 21103501 + ... + 21103540.

It is an arithmetic number, because the mean of its divisors is an integer number (147724647).

Almost surely, 2^844140820 is an apocalyptic number.

It is an amenable number.

844140820 is an abundant number, since it is smaller than the sum of its proper divisors (928554944).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

844140820 is a wasteful number, since it uses less digits than its factorization.

844140820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42207050 (or 42207048 counting only the distinct ones).

The product of its (nonzero) digits is 8192, while the sum is 31.

The square root of 844140820 is about 29054.1016037323. The cubic root of 844140820 is about 945.0866618918.

The spelling of 844140820 in words is "eight hundred forty-four million, one hundred forty thousand, eight hundred twenty".