64478649 has 4 divisors (see below), whose sum is σ = 85971536. Its totient is φ = 42985764.

The previous prime is 64478641. The next prime is 64478663. The reversal of 64478649 is 94687446.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 64478649 - 2³ = 64478641 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 64478598 and 64478607.

It is not an unprimeable number, because it can be changed into a prime (64478641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10746439 + ... + 10746444.

It is an arithmetic number, because the mean of its divisors is an integer number (21492884).

Almost surely, 2^64478649 is an apocalyptic number.

It is an amenable number.

64478649 is a deficient number, since it is larger than the sum of its proper divisors (21492887).

64478649 is a wasteful number, since it uses less digits than its factorization.

64478649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21492886.

The product of its digits is 1161216, while the sum is 48.

The square root of 64478649 is about 8029.8598368838. The cubic root of 64478649 is about 400.9947097475.

The spelling of 64478649 in words is "sixty-four million, four hundred seventy-eight thousand, six hundred forty-nine".