8538221540 has 24 divisors (see below), whose sum is σ = 17962136640. Its totient is φ = 3409217888.

The previous prime is 8538221509. The next prime is 8538221543. The reversal of 8538221540 is 451228358.

It is a super-2 number, since 2×8538221540² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 8538221494 and 8538221503.

It is not an unprimeable number, because it can be changed into a prime (8538221543) 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, 367880 + ... + 390399.

It is an arithmetic number, because the mean of its divisors is an integer number (748422360).

Almost surely, 2^8538221540 is an apocalyptic number.

It is an amenable number.

8538221540 is an abundant number, since it is smaller than the sum of its proper divisors (9423915100).

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

8538221540 is a wasteful number, since it uses less digits than its factorization.

8538221540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 758851 (or 758849 counting only the distinct ones).

The product of its (nonzero) digits is 76800, while the sum is 38.

The square root of 8538221540 is about 92402.4974770704. The cubic root of 8538221540 is about 2043.8819409500.

Adding to 8538221540 its reverse (451228358), we get a palindrome (8989449898).

The spelling of 8538221540 in words is "eight billion, five hundred thirty-eight million, two hundred twenty-one thousand, five hundred forty".