161689660 has 24 divisors (see below), whose sum is σ = 370416816. Its totient is φ = 58796160.

The previous prime is 161689631. The next prime is 161689673. The reversal of 161689660 is 66986161.

It is a happy number.

161689660 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×161689660² = 52287092301831200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 367257 + ... + 367696.

It is an arithmetic number, because the mean of its divisors is an integer number (15434034).

Almost surely, 2^161689660 is an apocalyptic number.

161689660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161689660 is an abundant number, since it is smaller than the sum of its proper divisors (208727156).

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

161689660 is a wasteful number, since it uses less digits than its factorization.

161689660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 734973 (or 734971 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 43.

The square root of 161689660 is about 12715.7249105193. The cubic root of 161689660 is about 544.7878533506.

The spelling of 161689660 in words is "one hundred sixty-one million, six hundred eighty-nine thousand, six hundred sixty".