161699 has 4 divisors (see below), whose sum is σ = 163464. Its totient is φ = 159936.

The previous prime is 161683. The next prime is 161717. The reversal of 161699 is 996161.

161699 = T₂ + T₃ + ... + T₉₈.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 161699 - 2⁴ = 161683 is a prime.

It is a super-2 number, since 2×161699² = 52293133202, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 161699.

It is not an unprimeable number, because it can be changed into a prime (161639) 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 3 ways as a sum of consecutive naturals, for example, 737 + ... + 930.

It is an arithmetic number, because the mean of its divisors is an integer number (40866).

2¹⁶¹⁶⁹⁹ is an apocalyptic number.

161699 is a deficient number, since it is larger than the sum of its proper divisors (1765).

161699 is an equidigital number, since it uses as much as digits as its factorization.

161699 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1764.

The product of its digits is 2916, while the sum is 32.

The square root of 161699 is about 402.1181418439. The cubic root of 161699 is about 54.4798343035.

The spelling of 161699 in words is "one hundred sixty-one thousand, six hundred ninety-nine".