166561633 has 12 divisors (see below), whose sum is σ = 194080212. Its totient is φ = 142527840.

The previous prime is 166561613. The next prime is 166561649. The reversal of 166561633 is 336165661.

It can be written as a sum of positive squares in 2 ways, for example, as 160351569 + 6210064 = 12663^2 + 2492^2 .

It is not a de Polignac number, because 166561633 - 2¹³ = 166553441 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 166561592 and 166561601.

It is not an unprimeable number, because it can be changed into a prime (166561613) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30663 + ... + 35683.

It is an arithmetic number, because the mean of its divisors is an integer number (16173351).

Almost surely, 2^166561633 is an apocalyptic number.

It is an amenable number.

166561633 is a deficient number, since it is larger than the sum of its proper divisors (27518579).

166561633 is an equidigital number, since it uses as much as digits as its factorization.

166561633 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5712 (or 5705 counting only the distinct ones).

The product of its digits is 58320, while the sum is 37.

The square root of 166561633 is about 12905.8759098327. The cubic root of 166561633 is about 550.2055793472.

The spelling of 166561633 in words is "one hundred sixty-six million, five hundred sixty-one thousand, six hundred thirty-three".