64350721 has 4 divisors (see below), whose sum is σ = 64468912. Its totient is φ = 64232532.

The previous prime is 64350709. The next prime is 64350731. The reversal of 64350721 is 12705346.

64350721 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, and also an emirpimes, since its reverse is a distinct semiprime: 12705346 = 2 ⋅6352673.

It is a cyclic number.

It is not a de Polignac number, because 64350721 - 2¹¹ = 64348673 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 64350721.

It is not an unprimeable number, because it can be changed into a prime (64350731) 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, 58275 + ... + 59368.

It is an arithmetic number, because the mean of its divisors is an integer number (16117228).

Almost surely, 2^64350721 is an apocalyptic number.

It is an amenable number.

64350721 is a deficient number, since it is larger than the sum of its proper divisors (118191).

64350721 is a wasteful number, since it uses less digits than its factorization.

64350721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118190.

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 64350721 is about 8021.8901139320. The cubic root of 64350721 is about 400.7293381066.

The spelling of 64350721 in words is "sixty-four million, three hundred fifty thousand, seven hundred twenty-one".