161705642 has 16 divisors (see below), whose sum is σ = 279755520. Its totient is φ = 68665968.

The previous prime is 161705633. The next prime is 161705647. The reversal of 161705642 is 246507161.

It is a super-2 number, since 2×161705642² = 52297429309264328, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161705599 and 161705608.

It is not an unprimeable number, because it can be changed into a prime (161705647) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51458 + ... + 54509.

It is an arithmetic number, because the mean of its divisors is an integer number (17484720).

Almost surely, 2^161705642 is an apocalyptic number.

161705642 is a deficient number, since it is larger than the sum of its proper divisors (118049878).

161705642 is a wasteful number, since it uses less digits than its factorization.

161705642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106085.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 161705642 is about 12716.3533294730. The cubic root of 161705642 is about 544.8058023702.

It can be divided in two parts, 16170 and 5642, that added together give a palindrome (21812).

The spelling of 161705642 in words is "one hundred sixty-one million, seven hundred five thousand, six hundred forty-two".