161256610313220 has 192 divisors, whose sum is σ = 482900866076160. Its totient is φ = 40107309158400.

The previous prime is 161256610313213. The next prime is 161256610313233. The reversal of 161256610313220 is 22313016652161.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 104529646 + ... + 106061114.

It is an arithmetic number, because the mean of its divisors is an integer number (2515108677480).

Almost surely, 2^{161256610313220} is an apocalyptic number.

161256610313220 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 161256610313220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (241450433038080).

161256610313220 is an abundant number, since it is smaller than the sum of its proper divisors (321644255762940).

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

161256610313220 is a wasteful number, since it uses less digits than its factorization.

161256610313220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1533406 (or 1533404 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 39.

Adding to 161256610313220 its reverse (22313016652161), we get a palindrome (183569626965381).

The spelling of 161256610313220 in words is "one hundred sixty-one trillion, two hundred fifty-six billion, six hundred ten million, three hundred thirteen thousand, two hundred twenty".