521522643 has 4 divisors (see below), whose sum is σ = 695363528. Its totient is φ = 347681760.

The previous prime is 521522633. The next prime is 521522663. The reversal of 521522643 is 346225125.

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

It is not a de Polignac number, because 521522643 - 2⁴ = 521522627 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 521522643.

It is not an unprimeable number, because it can be changed into a prime (521522633) 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, 86920438 + ... + 86920443.

It is an arithmetic number, because the mean of its divisors is an integer number (173840882).

Almost surely, 2^521522643 is an apocalyptic number.

521522643 is a deficient number, since it is larger than the sum of its proper divisors (173840885).

521522643 is a wasteful number, since it uses less digits than its factorization.

521522643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173840884.

The product of its digits is 14400, while the sum is 30.

The square root of 521522643 is about 22836.8702540431. The cubic root of 521522643 is about 804.9292753215.

Adding to 521522643 its reverse (346225125), we get a palindrome (867747768).

The spelling of 521522643 in words is "five hundred twenty-one million, five hundred twenty-two thousand, six hundred forty-three".