64021385 has 4 divisors (see below), whose sum is σ = 76825668. Its totient is φ = 51217104.

The previous prime is 64021369. The next prime is 64021387. The reversal of 64021385 is 58312046.

64021385 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 12411529 + 51609856 = 3523^2 + 7184^2 .

It is a cyclic number.

It is not a de Polignac number, because 64021385 - 2⁴ = 64021369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64021387) by changing a digit.

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, 6402134 + ... + 6402143.

It is an arithmetic number, because the mean of its divisors is an integer number (19206417).

Almost surely, 2^64021385 is an apocalyptic number.

It is an amenable number.

64021385 is a deficient number, since it is larger than the sum of its proper divisors (12804283).

64021385 is a wasteful number, since it uses less digits than its factorization.

64021385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12804282.

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 64021385 is about 8001.3364508687. The cubic root of 64021385 is about 400.0445471220.

The spelling of 64021385 in words is "sixty-four million, twenty-one thousand, three hundred eighty-five".