168409513 has 4 divisors (see below), whose sum is σ = 168721348. Its totient is φ = 168097680.

The previous prime is 168409511. The next prime is 168409517. The reversal of 168409513 is 315904861.

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 80856064 + 87553449 = 8992^2 + 9357^2 .

It is a cyclic number.

It is not a de Polignac number, because 168409513 - 2¹ = 168409511 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (168409511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 155106 + ... + 156187.

It is an arithmetic number, because the mean of its divisors is an integer number (42180337).

Almost surely, 2^168409513 is an apocalyptic number.

It is an amenable number.

168409513 is a deficient number, since it is larger than the sum of its proper divisors (311835).

168409513 is an equidigital number, since it uses as much as digits as its factorization.

168409513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 311834.

The product of its (nonzero) digits is 25920, while the sum is 37.

The square root of 168409513 is about 12977.2690886796. The cubic root of 168409513 is about 552.2328108926.

The spelling of 168409513 in words is "one hundred sixty-eight million, four hundred nine thousand, five hundred thirteen".