161555623788 has 96 divisors (see below), whose sum is σ = 433943096832. Its totient is φ = 46388390400.

The previous prime is 161555623777. The next prime is 161555623793. The reversal of 161555623788 is 887326555161.

It is a super-2 number, since 2×161555623788² (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 (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 401998 + ... + 696213.

It is an arithmetic number, because the mean of its divisors is an integer number (4520240592).

Almost surely, 2^161555623788 is an apocalyptic number.

It is an amenable number.

161555623788 is an abundant number, since it is smaller than the sum of its proper divisors (272387473044).

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

161555623788 is a wasteful number, since it uses less digits than its factorization.

161555623788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1098295 (or 1098293 counting only the distinct ones).

The product of its digits is 12096000, while the sum is 57.

The spelling of 161555623788 in words is "one hundred sixty-one billion, five hundred fifty-five million, six hundred twenty-three thousand, seven hundred eighty-eight".