8220440642 has 18 divisors (see below), whose sum is σ = 12548055897. Its totient is φ = 4038993000.

The previous prime is 8220440623. The next prime is 8220440647. The reversal of 8220440642 is 2460440228.

It can be written as a sum of positive squares in 2 ways, for example, as 5568293641 + 2652147001 = 74621^2 + 51499^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=64111.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 8220440599 and 8220440608.

It is not an unprimeable number, because it can be changed into a prime (8220440647) 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 8 ways as a sum of consecutive naturals, for example, 7821017 + ... + 7822067.

Almost surely, 2^8220440642 is an apocalyptic number.

8220440642 is a deficient number, since it is larger than the sum of its proper divisors (4327615255).

8220440642 is an frugal number, since it uses more digits than its factorization.

8220440642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2226 (or 1114 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 32.

The square root of 8220440642 is about 90666.6456973015. The cubic root of 8220440642 is about 2018.2038605305.

Multiplying 8220440642 by its sum of digits (32), we get a square (263054100544 = 512888²).

The spelling of 8220440642 in words is "eight billion, two hundred twenty million, four hundred forty thousand, six hundred forty-two".