161209798888320 has 2688 divisors, whose sum is σ = 761992316820000. Its totient is φ = 32222183325696.

The previous prime is 161209798888319. The next prime is 161209798888351. The reversal of 161209798888320 is 23888897902161.

161209798888320 is a `hidden beast` number, since 1 + 6 + 1 + 209 + 7 + 98 + 8 + 8 + 8 + 320 = 666.

It is a tau number, because it is divible by the number of its divisors (2688).

It is a super-2 number, since 2×161209798888320² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 335 ways as a sum of consecutive naturals, for example, 5646761406 + ... + 5646789954.

Almost surely, 2^{161209798888320} is an apocalyptic number.

161209798888320 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 161209798888320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (380996158410000).

161209798888320 is an abundant number, since it is smaller than the sum of its proper divisors (600782517931680).

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

161209798888320 is a wasteful number, since it uses less digits than its factorization.

161209798888320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28632 (or 28598 counting only the distinct ones).

The product of its (nonzero) digits is 167215104, while the sum is 72.

The spelling of 161209798888320 in words is "one hundred sixty-one trillion, two hundred nine billion, seven hundred ninety-eight million, eight hundred eighty-eight thousand, three hundred twenty".