80643638 has 32 divisors (see below), whose sum is σ = 131604480. Its totient is φ = 36936000.

The previous prime is 80643623. The next prime is 80643643. The reversal of 80643638 is 83634608.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 297443 + ... + 297713.

It is an arithmetic number, because the mean of its divisors is an integer number (4112640).

Almost surely, 2^80643638 is an apocalyptic number.

80643638 is a deficient number, since it is larger than the sum of its proper divisors (50960842).

80643638 is a wasteful number, since it uses less digits than its factorization.

80643638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 524.

The product of its (nonzero) digits is 82944, while the sum is 38.

The square root of 80643638 is about 8980.1802877225. The cubic root of 80643638 is about 432.0394161280.

It can be divided in two parts, 806 and 43638, that added together give a palindrome (44444).

The spelling of 80643638 in words is "eighty million, six hundred forty-three thousand, six hundred thirty-eight".