63644399 has 16 divisors (see below), whose sum is σ = 78962688. Its totient is φ = 49950432.

The previous prime is 63644389. The next prime is 63644419. The reversal of 63644399 is 99344636.

It is not a de Polignac number, because 63644399 - 2¹⁶ = 63578863 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63644369) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8804 + ... + 14310.

It is an arithmetic number, because the mean of its divisors is an integer number (4935168).

Almost surely, 2^63644399 is an apocalyptic number.

63644399 is a deficient number, since it is larger than the sum of its proper divisors (15318289).

63644399 is a wasteful number, since it uses less digits than its factorization.

63644399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5654.

The product of its digits is 419904, while the sum is 44.

The square root of 63644399 is about 7977.7439793465. The cubic root of 63644399 is about 399.2577882394.

The spelling of 63644399 in words is "sixty-three million, six hundred forty-four thousand, three hundred ninety-nine".