161993600 has 192 divisors, whose sum is σ = 437114880. Its totient is φ = 59136000.

The previous prime is 161993593. The next prime is 161993609. The reversal of 161993600 is 6399161.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161993609) 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 23 ways as a sum of consecutive naturals, for example, 2281565 + ... + 2281635.

It is an arithmetic number, because the mean of its divisors is an integer number (2276640).

Almost surely, 2^161993600 is an apocalyptic number.

161993600 is a gapful number since it is divisible by the number (10) 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 161993600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (218557440).

161993600 is an abundant number, since it is smaller than the sum of its proper divisors (275121280).

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

161993600 is a wasteful number, since it uses less digits than its factorization.

161993600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149 (or 132 counting only the distinct ones).

The product of its (nonzero) digits is 8748, while the sum is 35.

The square root of 161993600 is about 12727.6706431303. The cubic root of 161993600 is about 545.1289990071.

The spelling of 161993600 in words is "one hundred sixty-one million, nine hundred ninety-three thousand, six hundred".