64390945 has 4 divisors (see below), whose sum is σ = 77269140. Its totient is φ = 51512752.

The previous prime is 64390939. The next prime is 64390957. The reversal of 64390945 is 54909346.

64390945 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 20394256 + 43996689 = 4516^2 + 6633^2 .

It is a cyclic number.

It is not a de Polignac number, because 64390945 - 2⁵ = 64390913 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 64390898 and 64390907.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6439090 + ... + 6439099.

It is an arithmetic number, because the mean of its divisors is an integer number (19317285).

Almost surely, 2^64390945 is an apocalyptic number.

It is an amenable number.

64390945 is a deficient number, since it is larger than the sum of its proper divisors (12878195).

64390945 is a wasteful number, since it uses less digits than its factorization.

64390945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12878194.

The product of its (nonzero) digits is 116640, while the sum is 40.

The square root of 64390945 is about 8024.3968620701. The cubic root of 64390945 is about 400.8128159568.

The spelling of 64390945 in words is "sixty-four million, three hundred ninety thousand, nine hundred forty-five".