841638121 has 9 divisors (see below), whose sum is σ = 856365111. Its totient is φ = 827161632.

The previous prime is 841638107. The next prime is 841638143. The reversal of 841638121 is 121836148.

The square root of 841638121 is 29011.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 94381225 + 747256896 = 9715^2 + 27336^2 .

It is not a de Polignac number, because 841638121 - 2²³ = 833249513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (841638181) 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 8 ways as a sum of consecutive naturals, for example, 1943521 + ... + 1943953.

It is an arithmetic number, because the mean of its divisors is an integer number (95151679).

Almost surely, 2^841638121 is an apocalyptic number.

841638121 is the 29011-st square number.

841638121 is the 14506-th centered octagonal number.

It is an amenable number.

841638121 is a deficient number, since it is larger than the sum of its proper divisors (14726990).

841638121 is an frugal number, since it uses more digits than its factorization.

841638121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1000 (or 500 counting only the distinct ones).

The product of its digits is 9216, while the sum is 34.

The cubic root of 841638121 is about 944.1517433129.

Multiplying 841638121 by its product of digits (9216), we get a square (7756536923136 = 2785056²).

The spelling of 841638121 in words is "eight hundred forty-one million, six hundred thirty-eight thousand, one hundred twenty-one".