47691521 has 4 divisors (see below), whose sum is σ = 47732052. Its totient is φ = 47650992.

The previous prime is 47691499. The next prime is 47691559. The reversal of 47691521 is 12519674.

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 18800896 + 28890625 = 4336^2 + 5375^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-47691521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (47691221) 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, 18446 + ... + 20871.

It is an arithmetic number, because the mean of its divisors is an integer number (11933013).

Almost surely, 2^47691521 is an apocalyptic number.

It is an amenable number.

47691521 is a deficient number, since it is larger than the sum of its proper divisors (40531).

47691521 is a wasteful number, since it uses less digits than its factorization.

47691521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40530.

The product of its digits is 15120, while the sum is 35.

The square root of 47691521 is about 6905.9047922774. The cubic root of 47691521 is about 362.6439121025.

The spelling of 47691521 in words is "forty-seven million, six hundred ninety-one thousand, five hundred twenty-one".