161081403680 has 24 divisors (see below), whose sum is σ = 380554816572. Its totient is φ = 64432561408.

The previous prime is 161081403673. The next prime is 161081403709. The reversal of 161081403680 is 86304180161.

It can be written as a sum of positive squares in 2 ways, for example, as 152415283216 + 8666120464 = 390404^2 + 93092^2 .

It is a super-2 number, since 2×161081403680² (a number of 23 digits) contains 22 as substring.

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 3 ways as a sum of consecutive naturals, for example, 503379227 + ... + 503379546.

Almost surely, 2^161081403680 is an apocalyptic number.

161081403680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161081403680 is an abundant number, since it is smaller than the sum of its proper divisors (219473412892).

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

161081403680 is a wasteful number, since it uses less digits than its factorization.

161081403680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1006758788 (or 1006758780 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 38.

The spelling of 161081403680 in words is "one hundred sixty-one billion, eighty-one million, four hundred three thousand, six hundred eighty".