340808521 has 3 divisors (see below), whose sum is σ = 340826983. Its totient is φ = 340790060.

The previous prime is 340808519. The next prime is 340808527. The reversal of 340808521 is 125808043.

The square root of 340808521 is 18461.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 16088121 + 324720400 = 4011^2 + 18020^2 .

It is not a de Polignac number, because 340808521 - 2¹ = 340808519 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (340808527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 9231 + ... + 27691.

Almost surely, 2^340808521 is an apocalyptic number.

340808521 is the 18461-st square number.

340808521 is the 9231-st centered octagonal number.

It is an amenable number.

340808521 is a deficient number, since it is larger than the sum of its proper divisors (18462).

340808521 is an frugal number, since it uses more digits than its factorization.

340808521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36922 (or 18461 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 31.

The cubic root of 340808521 is about 698.5060116545.

The spelling of 340808521 in words is "three hundred forty million, eight hundred eight thousand, five hundred twenty-one".