63871919 has 4 divisors (see below), whose sum is σ = 65230944. Its totient is φ = 62512896.

The previous prime is 63871909. The next prime is 63871921. The reversal of 63871919 is 91917836.

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 63871919 - 2⁸ = 63871663 is a prime.

It is a super-2 number, since 2×63871919² = 8159244073485122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 63871919.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63871909) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 679442 + ... + 679535.

It is an arithmetic number, because the mean of its divisors is an integer number (16307736).

Almost surely, 2^63871919 is an apocalyptic number.

63871919 is a deficient number, since it is larger than the sum of its proper divisors (1359025).

63871919 is a wasteful number, since it uses less digits than its factorization.

63871919 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1359024.

The product of its digits is 81648, while the sum is 44.

The square root of 63871919 is about 7991.9909284233. The cubic root of 63871919 is about 399.7329863823.

The spelling of 63871919 in words is "sixty-three million, eight hundred seventy-one thousand, nine hundred nineteen".