161310320640 has 1080 divisors, whose sum is σ = 677263229370. Its totient is φ = 36870930432.

The previous prime is 161310320617. The next prime is 161310320653. The reversal of 161310320640 is 46023013161.

161310320640 is a `hidden beast` number, since 1 + 6 + 1 + 3 + 10 + 3 + 2 + 0 + 640 = 666.

It can be written as a sum of positive squares in only one way, i.e., 145179288576 + 16131032064 = 381024^2 + 127008^2 .

It is a tau number, because it is divible by the number of its divisors (1080).

It is a super-2 number, since 2×161310320640² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

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 89 ways as a sum of consecutive naturals, for example, 23044331517 + ... + 23044331523.

Almost surely, 2^161310320640 is an apocalyptic number.

161310320640 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 161310320640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (338631614685).

161310320640 is an abundant number, since it is smaller than the sum of its proper divisors (515952908730).

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

161310320640 is an frugal number, since it uses more digits than its factorization.

161310320640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79 (or 17 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The spelling of 161310320640 in words is "one hundred sixty-one billion, three hundred ten million, three hundred twenty thousand, six hundred forty".