8161638 has 16 divisors (see below), whose sum is σ = 16444080. Its totient is φ = 2700416.

The previous prime is 8161631. The next prime is 8161661. The reversal of 8161638 is 8361618.

It is a super-2 number, since 2×8161638² = 133224669686088, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 8161599 and 8161608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8161631) 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, 4143 + ... + 5786.

It is an arithmetic number, because the mean of its divisors is an integer number (1027755).

Almost surely, 2^8161638 is an apocalyptic number.

8161638 is an abundant number, since it is smaller than the sum of its proper divisors (8282442).

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

8161638 is a wasteful number, since it uses less digits than its factorization.

8161638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10071.

The product of its digits is 6912, while the sum is 33.

The square root of 8161638 is about 2856.8580643777. The cubic root of 8161638 is about 201.3380119911.

The spelling of 8161638 in words is "eight million, one hundred sixty-one thousand, six hundred thirty-eight".