63749891 has 4 divisors (see below), whose sum is σ = 63780912. Its totient is φ = 63718872.

The previous prime is 63749869. The next prime is 63749909. The reversal of 63749891 is 19894736.

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 63749891 - 2⁶ = 63749827 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (63749591) 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, 12191 + ... + 16616.

It is an arithmetic number, because the mean of its divisors is an integer number (15945228).

Almost surely, 2^63749891 is an apocalyptic number.

63749891 is a deficient number, since it is larger than the sum of its proper divisors (31021).

63749891 is a wasteful number, since it uses less digits than its factorization.

63749891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31020.

The product of its digits is 326592, while the sum is 47.

The square root of 63749891 is about 7984.3528854880. The cubic root of 63749891 is about 399.4782593459.

The spelling of 63749891 in words is "sixty-three million, seven hundred forty-nine thousand, eight hundred ninety-one".