63728191 has 4 divisors (see below), whose sum is σ = 64150384. Its totient is φ = 63306000.

The previous prime is 63728143. The next prime is 63728213. The reversal of 63728191 is 19182736.

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 63728191 - 2²¹ = 61631039 is a prime.

It is a super-2 number, since 2×63728191² = 8122564656264962, 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 63728191.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63728141) 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, 210870 + ... + 211171.

It is an arithmetic number, because the mean of its divisors is an integer number (16037596).

Almost surely, 2^63728191 is an apocalyptic number.

63728191 is a deficient number, since it is larger than the sum of its proper divisors (422193).

63728191 is a wasteful number, since it uses less digits than its factorization.

63728191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 422192.

The product of its digits is 18144, while the sum is 37.

The square root of 63728191 is about 7982.9938619543. The cubic root of 63728191 is about 399.4329277024.

The spelling of 63728191 in words is "sixty-three million, seven hundred twenty-eight thousand, one hundred ninety-one".