161645859 has 12 divisors (see below), whose sum is σ = 239799456. Its totient is φ = 104851152.

The previous prime is 161645857. The next prime is 161645867. The reversal of 161645859 is 958546161.

161645859 is a `hidden beast` number, since 1 + 6 + 1 + 64 + 585 + 9 = 666.

It is not a de Polignac number, because 161645859 - 2¹ = 161645857 is a prime.

It is a super-2 number, since 2×161645859² = 52258767463695762, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161645857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 242379 + ... + 243044.

It is an arithmetic number, because the mean of its divisors is an integer number (19983288).

Almost surely, 2^161645859 is an apocalyptic number.

161645859 is a deficient number, since it is larger than the sum of its proper divisors (78153597).

161645859 is a wasteful number, since it uses less digits than its factorization.

161645859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 485466 (or 485463 counting only the distinct ones).

The product of its digits is 259200, while the sum is 45.

The square root of 161645859 is about 12714.0024775835. The cubic root of 161645859 is about 544.7386553833.

The spelling of 161645859 in words is "one hundred sixty-one million, six hundred forty-five thousand, eight hundred fifty-nine".