521744401 has 4 divisors (see below), whose sum is σ = 521809204. Its totient is φ = 521679600.

The previous prime is 521744341. The next prime is 521744429. The reversal of 521744401 is 104447125.

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 360962001 + 160782400 = 18999^2 + 12680^2 .

It is a cyclic number.

It is not a de Polignac number, because 521744401 - 2¹⁹ = 521220113 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 521744401.

It is not an unprimeable number, because it can be changed into a prime (521744471) 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, 18270 + ... + 37111.

It is an arithmetic number, because the mean of its divisors is an integer number (130452301).

Almost surely, 2^521744401 is an apocalyptic number.

It is an amenable number.

521744401 is a deficient number, since it is larger than the sum of its proper divisors (64803).

521744401 is an equidigital number, since it uses as much as digits as its factorization.

521744401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64802.

The product of its (nonzero) digits is 4480, while the sum is 28.

The square root of 521744401 is about 22841.7250005336. The cubic root of 521744401 is about 805.0433478451.

The spelling of 521744401 in words is "five hundred twenty-one million, seven hundred forty-four thousand, four hundred one".