64780778 has 8 divisors (see below), whose sum is σ = 102887172. Its totient is φ = 30485056.

The previous prime is 64780777. The next prime is 64780783. The reversal of 64780778 is 87708746.

It can be written as a sum of positive squares in 2 ways, for example, as 64754209 + 26569 = 8047^2 + 163^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (64780777) 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 in 3 ways as a sum of consecutive naturals, for example, 952625 + ... + 952692.

Almost surely, 2^64780778 is an apocalyptic number.

64780778 is a deficient number, since it is larger than the sum of its proper divisors (38106394).

64780778 is a wasteful number, since it uses less digits than its factorization.

64780778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1905336.

The product of its (nonzero) digits is 526848, while the sum is 47.

The square root of 64780778 is about 8048.6506943711. The cubic root of 64780778 is about 401.6200505656.

The spelling of 64780778 in words is "sixty-four million, seven hundred eighty thousand, seven hundred seventy-eight".