521340042109 has 8 divisors (see below), whose sum is σ = 522739554680. Its totient is φ = 519941431296.

The previous prime is 521340042107. The next prime is 521340042163. The reversal of 521340042109 is 901240043125.

It can be written as a sum of positive squares in 4 ways, for example, as 30772878084 + 490567164025 = 175422^2 + 700405^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 521340042109 - 2¹ = 521340042107 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521340042107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 940459 + ... + 1388215.

It is an arithmetic number, because the mean of its divisors is an integer number (65342444335).

Almost surely, 2^521340042109 is an apocalyptic number.

It is an amenable number.

521340042109 is a deficient number, since it is larger than the sum of its proper divisors (1399512571).

521340042109 is a wasteful number, since it uses less digits than its factorization.

521340042109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 450879.

The product of its (nonzero) digits is 8640, while the sum is 31.

The spelling of 521340042109 in words is "five hundred twenty-one billion, three hundred forty million, forty-two thousand, one hundred nine".