521221489 has 4 divisors (see below), whose sum is σ = 522561780. Its totient is φ = 519881200.

The previous prime is 521221487. The next prime is 521221511. The reversal of 521221489 is 984122125.

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 278890000 + 242331489 = 16700^2 + 15567^2 .

It is a cyclic number.

It is not a de Polignac number, because 521221489 - 2¹ = 521221487 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (521221483) 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, 669562 + ... + 670339.

It is an arithmetic number, because the mean of its divisors is an integer number (130640445).

Almost surely, 2^521221489 is an apocalyptic number.

It is an amenable number.

521221489 is a deficient number, since it is larger than the sum of its proper divisors (1340291).

521221489 is a wasteful number, since it uses less digits than its factorization.

521221489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1340290.

The product of its digits is 11520, while the sum is 34.

The square root of 521221489 is about 22830.2757101179. The cubic root of 521221489 is about 804.7743096335.

The spelling of 521221489 in words is "five hundred twenty-one million, two hundred twenty-one thousand, four hundred eighty-nine".