821634041 has 4 divisors (see below), whose sum is σ = 822312612. Its totient is φ = 820955472.

The previous prime is 821634029. The next prime is 821634097. The reversal of 821634041 is 140436128.

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 197683600 + 623950441 = 14060^2 + 24979^2 .

It is a cyclic number.

It is not a de Polignac number, because 821634041 - 2⁶ = 821633977 is a prime.

It is a super-3 number, since 3×821634041³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 821633995 and 821634013.

It is not an unprimeable number, because it can be changed into a prime (821636041) 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 3 ways as a sum of consecutive naturals, for example, 337466 + ... + 339891.

It is an arithmetic number, because the mean of its divisors is an integer number (205578153).

Almost surely, 2^821634041 is an apocalyptic number.

It is an amenable number.

821634041 is a deficient number, since it is larger than the sum of its proper divisors (678571).

821634041 is a wasteful number, since it uses less digits than its factorization.

821634041 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 678570.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 821634041 is about 28664.1595202092. The cubic root of 821634041 is about 936.6114759312.

The spelling of 821634041 in words is "eight hundred twenty-one million, six hundred thirty-four thousand, forty-one".