8501806638 has 48 divisors (see below), whose sum is σ = 20211871680. Its totient is φ = 2566579392.

The previous prime is 8501806631. The next prime is 8501806657. The reversal of 8501806638 is 8366081058.

8501806638 is a `hidden beast` number, since 8 + 5 + 0 + 1 + 8 + 0 + 6 + 638 = 666.

It is a super-2 number, since 2×8501806638² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 8501806593 and 8501806602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8501806631) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 330358 + ... + 355161.

It is an arithmetic number, because the mean of its divisors is an integer number (421080660).

Almost surely, 2^8501806638 is an apocalyptic number.

8501806638 is an abundant number, since it is smaller than the sum of its proper divisors (11710065042).

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

8501806638 is a wasteful number, since it uses less digits than its factorization.

8501806638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 685593 (or 685590 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The square root of 8501806638 is about 92205.2419225718. The cubic root of 8501806638 is about 2040.9721303867.

The spelling of 8501806638 in words is "eight billion, five hundred one million, eight hundred six thousand, six hundred thirty-eight".