838541821 has 4 divisors (see below), whose sum is σ = 903045052. Its totient is φ = 774038592.

The previous prime is 838541749. The next prime is 838541831. The reversal of 838541821 is 128145838.

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 70476025 + 768065796 = 8395^2 + 27714^2 .

It is a cyclic number.

It is not a de Polignac number, because 838541821 - 2⁹ = 838541309 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (838541831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32251596 + ... + 32251621.

It is an arithmetic number, because the mean of its divisors is an integer number (225761263).

Almost surely, 2^838541821 is an apocalyptic number.

It is an amenable number.

838541821 is a deficient number, since it is larger than the sum of its proper divisors (64503231).

838541821 is a wasteful number, since it uses less digits than its factorization.

838541821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64503230.

The product of its digits is 61440, while the sum is 40.

The square root of 838541821 is about 28957.5865879738. The cubic root of 838541821 is about 942.9925082256.

The spelling of 838541821 in words is "eight hundred thirty-eight million, five hundred forty-one thousand, eight hundred twenty-one".