64263521 has 4 divisors (see below), whose sum is σ = 73444032. Its totient is φ = 55083012.

The previous prime is 64263509. The next prime is 64263547. The reversal of 64263521 is 12536246.

64263521 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, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 64263521 - 2¹⁴ = 64247137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64263571) 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, 4590245 + ... + 4590258.

It is an arithmetic number, because the mean of its divisors is an integer number (18361008).

Almost surely, 2^64263521 is an apocalyptic number.

It is an amenable number.

64263521 is a deficient number, since it is larger than the sum of its proper divisors (9180511).

64263521 is an equidigital number, since it uses as much as digits as its factorization.

64263521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9180510.

The product of its digits is 8640, while the sum is 29.

The square root of 64263521 is about 8016.4531433796. The cubic root of 64263521 is about 400.5482502941.

Adding to 64263521 its reverse (12536246), we get a palindrome (76799767).

The spelling of 64263521 in words is "sixty-four million, two hundred sixty-three thousand, five hundred twenty-one".