161064581 has 2 divisors, whose sum is σ = 161064582. Its totient is φ = 161064580.

The previous prime is 161064569. The next prime is 161064593. The reversal of 161064581 is 185460161.

It is a balanced prime because it is at equal distance from previous prime (161064569) and next prime (161064593).

It can be written as a sum of positive squares in only one way, i.e., 149842081 + 11222500 = 12241^2 + 3350^2 .

It is a cyclic number.

It is not a de Polignac number, because 161064581 - 2¹⁰ = 161063557 is a prime.

It is a super-2 number, since 2×161064581² = 51883598505411122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161064551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80532290 + 80532291.

It is an arithmetic number, because the mean of its divisors is an integer number (80532291).

Almost surely, 2^161064581 is an apocalyptic number.

It is an amenable number.

161064581 is a deficient number, since it is larger than the sum of its proper divisors (1).

161064581 is an equidigital number, since it uses as much as digits as its factorization.

161064581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 161064581 is about 12691.1221332079. The cubic root of 161064581 is about 544.0849116393.

It can be divided in two parts, 1610 and 64581, that multiplied together give a triangular number (103975410 = T₁₄₄₂₀).

The spelling of 161064581 in words is "one hundred sixty-one million, sixty-four thousand, five hundred eighty-one".