63639 has 8 divisors (see below), whose sum is σ = 94320. Its totient is φ = 42408.

The previous prime is 63629. The next prime is 63647. The reversal of 63639 is 93636.

It is not a de Polignac number, because 63639 - 2⁵ = 63607 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 2357 = 63639 / (6 + 3 + 6 + 3 + 9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63629) 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, 1152 + ... + 1205.

It is an arithmetic number, because the mean of its divisors is an integer number (11790).

2⁶³⁶³⁹ is an apocalyptic number.

63639 is a deficient number, since it is larger than the sum of its proper divisors (30681).

63639 is a wasteful number, since it uses less digits than its factorization.

63639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2366 (or 2360 counting only the distinct ones).

The product of its digits is 2916, while the sum is 27.

The square root of 63639 is about 252.2677149379. The cubic root of 63639 is about 39.9246498145.

The spelling of 63639 in words is "sixty-three thousand, six hundred thirty-nine".