168226561 has 6 divisors (see below), whose sum is σ = 168821250. Its totient is φ = 167633856.

The previous prime is 168226519. The next prime is 168226573. The reversal of 168226561 is 165622861.

It can be written as a sum of positive squares in only one way, i.e., 137921536 + 30305025 = 11744^2 + 5505^2 .

It is not a de Polignac number, because 168226561 - 2⁷ = 168226433 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 168226561.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (168226661) 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, 134065 + ... + 135313.

It is an arithmetic number, because the mean of its divisors is an integer number (28136875).

Almost surely, 2^168226561 is an apocalyptic number.

It is an amenable number.

168226561 is a deficient number, since it is larger than the sum of its proper divisors (594689).

168226561 is an frugal number, since it uses more digits than its factorization.

168226561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1983 (or 1616 counting only the distinct ones).

The product of its digits is 34560, while the sum is 37.

The square root of 168226561 is about 12970.2182325511. The cubic root of 168226561 is about 552.0327653746.

The spelling of 168226561 in words is "one hundred sixty-eight million, two hundred twenty-six thousand, five hundred sixty-one".