47521813 has 4 divisors (see below), whose sum is σ = 47992428. Its totient is φ = 47051200.

The previous prime is 47521781. The next prime is 47521819. The reversal of 47521813 is 31812574.

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 23882769 + 23639044 = 4887^2 + 4862^2 .

It is a cyclic number.

It is not a de Polignac number, because 47521813 - 2⁵ = 47521781 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (47521819) 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, 235156 + ... + 235357.

It is an arithmetic number, because the mean of its divisors is an integer number (11998107).

Almost surely, 2^47521813 is an apocalyptic number.

It is an amenable number.

47521813 is a deficient number, since it is larger than the sum of its proper divisors (470615).

47521813 is a wasteful number, since it uses less digits than its factorization.

47521813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 470614.

The product of its digits is 6720, while the sum is 31.

The square root of 47521813 is about 6893.6066757540. The cubic root of 47521813 is about 362.2132505204.

The spelling of 47521813 in words is "forty-seven million, five hundred twenty-one thousand, eight hundred thirteen".