521893663 has 2 divisors, whose sum is σ = 521893664. Its totient is φ = 521893662.

The previous prime is 521893661. The next prime is 521893721. The reversal of 521893663 is 366398125.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 521893663 - 2¹ = 521893661 is a prime.

Together with 521893661, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (521893661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260946831 + 260946832.

It is an arithmetic number, because the mean of its divisors is an integer number (260946832).

Almost surely, 2^521893663 is an apocalyptic number.

521893663 is a deficient number, since it is larger than the sum of its proper divisors (1).

521893663 is an equidigital number, since it uses as much as digits as its factorization.

521893663 is an evil number, because the sum of its binary digits is even.

The product of its digits is 233280, while the sum is 43.

The square root of 521893663 is about 22844.9920770396. The cubic root of 521893663 is about 805.1201101595.

The spelling of 521893663 in words is "five hundred twenty-one million, eight hundred ninety-three thousand, six hundred sixty-three".