63649778 has 4 divisors (see below), whose sum is σ = 95474670. Its totient is φ = 31824888.

The previous prime is 63649771. The next prime is 63649793. The reversal of 63649778 is 87794636.

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

It can be written as a sum of positive squares in only one way, i.e., 56957209 + 6692569 = 7547^2 + 2587^2 .

It is not an unprimeable number, because it can be changed into a prime (63649771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15912443 + ... + 15912446.

Almost surely, 2^63649778 is an apocalyptic number.

63649778 is a deficient number, since it is larger than the sum of its proper divisors (31824892).

63649778 is a wasteful number, since it uses less digits than its factorization.

63649778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31824891.

The product of its digits is 1524096, while the sum is 50.

The square root of 63649778 is about 7978.0810976074. The cubic root of 63649778 is about 399.2690358756.

The spelling of 63649778 in words is "sixty-three million, six hundred forty-nine thousand, seven hundred seventy-eight".