521742663 has 12 divisors (see below), whose sum is σ = 811599880. Its totient is φ = 321072336.

The previous prime is 521742659. The next prime is 521742673. The reversal of 521742663 is 366247125.

521742663 is a `hidden beast` number, since 521 + 74 + 2 + 6 + 63 = 666.

It is not a de Polignac number, because 521742663 - 2² = 521742659 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521742643) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2229553 + ... + 2229786.

Almost surely, 2^521742663 is an apocalyptic number.

521742663 is a deficient number, since it is larger than the sum of its proper divisors (289857217).

521742663 is a wasteful number, since it uses less digits than its factorization.

521742663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4459358 (or 4459355 counting only the distinct ones).

The product of its digits is 60480, while the sum is 36.

The square root of 521742663 is about 22841.6869560897. The cubic root of 521742663 is about 805.0424539420.

Adding to 521742663 its reverse (366247125), we get a palindrome (887989788).

The spelling of 521742663 in words is "five hundred twenty-one million, seven hundred forty-two thousand, six hundred sixty-three".