161649986601600 has 2304 divisors, whose sum is σ = 720152775129600. Its totient is φ = 35269845811200.

The previous prime is 161649986601589. The next prime is 161649986601611. The reversal of 161649986601600 is 6106689946161.

161649986601600 is a `hidden beast` number, since 1 + 6 + 1 + 6 + 499 + 86 + 6 + 0 + 1 + 60 + 0 = 666.

161649986601600 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (161649986601589) and next prime (161649986601611).

It is a super-2 number, since 2×161649986601600² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 8302079865 + ... + 8302099335.

It is an arithmetic number, because the mean of its divisors is an integer number (312566308650).

Almost surely, 2^{161649986601600} is an apocalyptic number.

161649986601600 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 161649986601600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (360076387564800).

161649986601600 is an abundant number, since it is smaller than the sum of its proper divisors (558502788528000).

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

161649986601600 is a wasteful number, since it uses less digits than its factorization.

161649986601600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19608 (or 19578 counting only the distinct ones).

The product of its (nonzero) digits is 20155392, while the sum is 63.

The spelling of 161649986601600 in words is "one hundred sixty-one trillion, six hundred forty-nine billion, nine hundred eighty-six million, six hundred one thousand, six hundred".