64728553 has 4 divisors (see below), whose sum is σ = 64788868. Its totient is φ = 64668240.

The previous prime is 64728523. The next prime is 64728581. The reversal of 64728553 is 35582746.

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 47155689 + 17572864 = 6867^2 + 4192^2 .

It is a cyclic number.

It is not a de Polignac number, because 64728553 - 2¹³ = 64720361 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64728523) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28518 + ... + 30703.

It is an arithmetic number, because the mean of its divisors is an integer number (16197217).

Almost surely, 2^64728553 is an apocalyptic number.

It is an amenable number.

64728553 is a deficient number, since it is larger than the sum of its proper divisors (60315).

64728553 is a wasteful number, since it uses less digits than its factorization.

64728553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60314.

The product of its digits is 201600, while the sum is 40.

The square root of 64728553 is about 8045.4057076073. The cubic root of 64728553 is about 401.5120954655.

The spelling of 64728553 in words is "sixty-four million, seven hundred twenty-eight thousand, five hundred fifty-three".