161037221216256 has 2400 divisors, whose sum is σ = 624073055434752. Its totient is φ = 40171756584960.

The previous prime is 161037221216243. The next prime is 161037221216257. The reversal of 161037221216256 is 652612122730161.

161037221216256 is a `hidden beast` number, since 1 + 6 + 1 + 0 + 3 + 7 + 2 + 2 + 12 + 1 + 625 + 6 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161037221216257) by changing a digit.

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 159 ways as a sum of consecutive naturals, for example, 294400769775 + ... + 294400770321.

Almost surely, 2^{161037221216256} is an apocalyptic number.

161037221216256 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 161037221216256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (312036527717376).

161037221216256 is an abundant number, since it is smaller than the sum of its proper divisors (463035834218496).

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

161037221216256 is an equidigital number, since it uses as much as digits as its factorization.

161037221216256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 715 (or 680 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The spelling of 161037221216256 in words is "one hundred sixty-one trillion, thirty-seven billion, two hundred twenty-one million, two hundred sixteen thousand, two hundred fifty-six".