73639 has 4 divisors (see below), whose sum is σ = 74200. Its totient is φ = 73080.

The previous prime is 73637. The next prime is 73643. The reversal of 73639 is 93637.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 73639 - 2¹ = 73637 is a prime.

It is a Duffinian number.

73639 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (73637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37 + ... + 385.

It is an arithmetic number, because the mean of its divisors is an integer number (18550).

2⁷³⁶³⁹ is an apocalyptic number.

73639 is a deficient number, since it is larger than the sum of its proper divisors (561).

73639 is a wasteful number, since it uses less digits than its factorization.

73639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 560.

The product of its digits is 3402, while the sum is 28.

The square root of 73639 is about 271.3650677593. The cubic root of 73639 is about 41.9149829743.

The spelling of 73639 in words is "seventy-three thousand, six hundred thirty-nine".