3648735721 has 8 divisors (see below), whose sum is σ = 3866096520. Its totient is φ = 3431678208.

The previous prime is 3648735719. The next prime is 3648735731. The reversal of 3648735721 is 1275378463.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 289374121 + 3359361600 = 17011^2 + 57960^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 3648735721 - 2¹ = 3648735719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3648735731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 50806 + ... + 99391.

It is an arithmetic number, because the mean of its divisors is an integer number (483262065).

Almost surely, 2^3648735721 is an apocalyptic number.

It is an amenable number.

3648735721 is a deficient number, since it is larger than the sum of its proper divisors (217360799).

3648735721 is a wasteful number, since it uses less digits than its factorization.

3648735721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151643.

The product of its digits is 846720, while the sum is 46.

The square root of 3648735721 is about 60404.7657143044. The cubic root of 3648735721 is about 1539.5039332409.

The spelling of 3648735721 in words is "three billion, six hundred forty-eight million, seven hundred thirty-five thousand, seven hundred twenty-one".