8401216820 has 24 divisors (see below), whose sum is σ = 17659877928. Its totient is φ = 3357187200.

The previous prime is 8401216777. The next prime is 8401216823. The reversal of 8401216820 is 286121048.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 90706576 + 8310510244 = 9524^2 + 91162^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8401216823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 185291 + ... + 226130.

It is an arithmetic number, because the mean of its divisors is an integer number (735828247).

Almost surely, 2^8401216820 is an apocalyptic number.

It is an amenable number.

8401216820 is an abundant number, since it is smaller than the sum of its proper divisors (9258661108).

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

8401216820 is a wasteful number, since it uses less digits than its factorization.

8401216820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 412451 (or 412449 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 32.

The square root of 8401216820 is about 91658.1519560590. The cubic root of 8401216820 is about 2032.8908653520.

Adding to 8401216820 its reverse (286121048), we get a palindrome (8687337868).

The spelling of 8401216820 in words is "eight billion, four hundred one million, two hundred sixteen thousand, eight hundred twenty".