8638641 has 24 divisors (see below), whose sum is σ = 13815360. Its totient is φ = 5157600.

The previous prime is 8638633. The next prime is 8638661. The reversal of 8638641 is 1468368.

It is a happy number.

8638641 is a `hidden beast` number, since 8 + 6 + 3 + 8 + 641 = 666.

It is not a de Polignac number, because 8638641 - 2³ = 8638633 is a prime.

It is a super-2 number, since 2×8638641² = 149252236653762, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 8638596 and 8638605.

It is not an unprimeable number, because it can be changed into a prime (8638621) 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, 6415 + ... + 7643.

It is an arithmetic number, because the mean of its divisors is an integer number (575640).

Almost surely, 2^8638641 is an apocalyptic number.

It is an amenable number.

8638641 is a deficient number, since it is larger than the sum of its proper divisors (5176719).

8638641 is a wasteful number, since it uses less digits than its factorization.

8638641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1317 (or 1314 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The square root of 8638641 is about 2939.1565116543. The cubic root of 8638641 is about 205.1863544384.

The spelling of 8638641 in words is "eight million, six hundred thirty-eight thousand, six hundred forty-one".