161660259 has 16 divisors (see below), whose sum is σ = 253585440. Its totient is φ = 101433600.

The previous prime is 161660221. The next prime is 161660267. The reversal of 161660259 is 952066161.

It is not a de Polignac number, because 161660259 - 2⁷ = 161660131 is a prime.

It is a super-2 number, since 2×161660259² = 52268078679894162, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161660209) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 175642 + ... + 176559.

It is an arithmetic number, because the mean of its divisors is an integer number (15849090).

Almost surely, 2^161660259 is an apocalyptic number.

161660259 is a deficient number, since it is larger than the sum of its proper divisors (91925181).

161660259 is a wasteful number, since it uses less digits than its factorization.

161660259 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 352227 (or 352221 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The square root of 161660259 is about 12714.5687697224. The cubic root of 161660259 is about 544.7548306687.

The spelling of 161660259 in words is "one hundred sixty-one million, six hundred sixty thousand, two hundred fifty-nine".