161993696 has 72 divisors (see below), whose sum is σ = 346603320. Its totient is φ = 74462976.

The previous prime is 161993647. The next prime is 161993701. The reversal of 161993696 is 696399161.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 427235 + ... + 427613.

It is an arithmetic number, because the mean of its divisors is an integer number (4813935).

Almost surely, 2^161993696 is an apocalyptic number.

161993696 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161993696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (173301660).

161993696 is an abundant number, since it is smaller than the sum of its proper divisors (184609624).

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

161993696 is a wasteful number, since it uses less digits than its factorization.

161993696 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 464 (or 437 counting only the distinct ones).

The product of its digits is 472392, while the sum is 50.

The square root of 161993696 is about 12727.6744144404. The cubic root of 161993696 is about 545.1291066911.

The spelling of 161993696 in words is "one hundred sixty-one million, nine hundred ninety-three thousand, six hundred ninety-six".