168721845 has 8 divisors (see below), whose sum is σ = 269954976. Its totient is φ = 89984976.

The previous prime is 168721831. The next prime is 168721849. The reversal of 168721845 is 548127861.

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

It is not a de Polignac number, because 168721845 - 2⁶ = 168721781 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 168721797 and 168721806.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (168721849) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5624047 + ... + 5624076.

It is an arithmetic number, because the mean of its divisors is an integer number (33744372).

Almost surely, 2^168721845 is an apocalyptic number.

168721845 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

168721845 is a deficient number, since it is larger than the sum of its proper divisors (101233131).

168721845 is a wasteful number, since it uses less digits than its factorization.

168721845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11248131.

The product of its digits is 107520, while the sum is 42.

The square root of 168721845 is about 12989.2973251058. The cubic root of 168721845 is about 552.5739900773.

It can be divided in two parts, 1687 and 21845, that added together give a palindrome (23532).

The spelling of 168721845 in words is "one hundred sixty-eight million, seven hundred twenty-one thousand, eight hundred forty-five".