161678190 has 64 divisors (see below), whose sum is σ = 406425600. Its totient is φ = 41107584.

The previous prime is 161678189. The next prime is 161678191. The reversal of 161678190 is 91876161.

It is an interprime number because it is at equal distance from previous prime (161678189) and next prime (161678191).

It is a super-2 number, since 2×161678190² = 52279674243352200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161678191) 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 in 31 ways as a sum of consecutive naturals, for example, 71091 + ... + 73329.

It is an arithmetic number, because the mean of its divisors is an integer number (6350400).

Almost surely, 2^161678190 is an apocalyptic number.

161678190 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 161678190, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (203212800).

161678190 is an abundant number, since it is smaller than the sum of its proper divisors (244747410).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161678190 is a wasteful number, since it uses less digits than its factorization.

161678190 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2361.

The product of its (nonzero) digits is 18144, while the sum is 39.

The square root of 161678190 is about 12715.2738861575. The cubic root of 161678190 is about 544.7749709263.

The spelling of 161678190 in words is "one hundred sixty-one million, six hundred seventy-eight thousand, one hundred ninety".