168521007 has 4 divisors (see below), whose sum is σ = 224694680. Its totient is φ = 112347336.

The previous prime is 168520951. The next prime is 168521009. The reversal of 168521007 is 700125861.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 168521007 - 2¹² = 168516911 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 (168521009) 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, 28086832 + ... + 28086837.

It is an arithmetic number, because the mean of its divisors is an integer number (56173670).

Almost surely, 2^168521007 is an apocalyptic number.

168521007 is a deficient number, since it is larger than the sum of its proper divisors (56173673).

168521007 is an equidigital number, since it uses as much as digits as its factorization.

168521007 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56173672.

The product of its (nonzero) digits is 3360, while the sum is 30.

The square root of 168521007 is about 12981.5641199356. The cubic root of 168521007 is about 552.3546509270.

Adding to 168521007 its reverse (700125861), we get a palindrome (868646868).

The spelling of 168521007 in words is "one hundred sixty-eight million, five hundred twenty-one thousand, seven".