521081247 has 4 divisors (see below), whose sum is σ = 694775000. Its totient is φ = 347387496.

The previous prime is 521081243. The next prime is 521081257. The reversal of 521081247 is 742180125.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 521081247 - 2² = 521081243 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 (521081243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86846872 + ... + 86846877.

It is an arithmetic number, because the mean of its divisors is an integer number (173693750).

Almost surely, 2^521081247 is an apocalyptic number.

521081247 is a deficient number, since it is larger than the sum of its proper divisors (173693753).

521081247 is a wasteful number, since it uses less digits than its factorization.

521081247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173693752.

The product of its (nonzero) digits is 4480, while the sum is 30.

The square root of 521081247 is about 22827.2040994950. The cubic root of 521081247 is about 804.7021245291.

The spelling of 521081247 in words is "five hundred twenty-one million, eighty-one thousand, two hundred forty-seven".