169721361 has 6 divisors (see below), whose sum is σ = 245153090. Its totient is φ = 113147568.

The previous prime is 169721359. The next prime is 169721399. The reversal of 169721361 is 163127961.

169721361 is nontrivially palindromic in base 8.

169721361 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 133541136 + 36180225 = 11556^2 + 6015^2 .

It is not a de Polignac number, because 169721361 - 2¹ = 169721359 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (169721561) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9428956 + ... + 9428973.

Almost surely, 2^169721361 is an apocalyptic number.

It is an amenable number.

169721361 is a deficient number, since it is larger than the sum of its proper divisors (75431729).

169721361 is a wasteful number, since it uses less digits than its factorization.

169721361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18857935 (or 18857932 counting only the distinct ones).

The product of its digits is 13608, while the sum is 36.

The square root of 169721361 is about 13027.7151104866. The cubic root of 169721361 is about 553.6630003943.

The spelling of 169721361 in words is "one hundred sixty-nine million, seven hundred twenty-one thousand, three hundred sixty-one".