63815 has 4 divisors (see below), whose sum is σ = 76584. Its totient is φ = 51048.

The previous prime is 63809. The next prime is 63823. The reversal of 63815 is 51836.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 63815 - 2⁴ = 63799 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 63815.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6377 + ... + 6386.

It is an arithmetic number, because the mean of its divisors is an integer number (19146).

2⁶³⁸¹⁵ is an apocalyptic number.

63815 is a deficient number, since it is larger than the sum of its proper divisors (12769).

63815 is a wasteful number, since it uses less digits than its factorization.

63815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12768.

The product of its digits is 720, while the sum is 23.

The square root of 63815 is about 252.6163098456. The cubic root of 63815 is about 39.9614211371.

It can be divided in two parts, 63 and 815, that added together give a palindrome (878).

The spelling of 63815 in words is "sixty-three thousand, eight hundred fifteen".