9538485721 has 4 divisors (see below), whose sum is σ = 9544108212. Its totient is φ = 9532863232.

The previous prime is 9538485689. The next prime is 9538485743. The reversal of 9538485721 is 1275848359.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1275848359 = 29 ⋅43994771.

It can be written as a sum of positive squares in 2 ways, for example, as 6932893696 + 2605592025 = 83264^2 + 51045^2 .

It is a cyclic number.

It is not a de Polignac number, because 9538485721 - 2⁵ = 9538485689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9538485751) 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, 2808700 + ... + 2812093.

It is an arithmetic number, because the mean of its divisors is an integer number (2386027053).

Almost surely, 2^9538485721 is an apocalyptic number.

It is an amenable number.

9538485721 is a deficient number, since it is larger than the sum of its proper divisors (5622491).

9538485721 is a wasteful number, since it uses less digits than its factorization.

9538485721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5622490.

The product of its digits is 2419200, while the sum is 52.

The square root of 9538485721 is about 97665.1714840045. The cubic root of 9538485721 is about 2120.7679163762.

The spelling of 9538485721 in words is "nine billion, five hundred thirty-eight million, four hundred eighty-five thousand, seven hundred twenty-one".