161555212708072 has 48 divisors (see below), whose sum is σ = 305211425371020. Its totient is φ = 80170067712000.

The previous prime is 161555212708063. The next prime is 161555212708079. The reversal of 161555212708072 is 270807212555161.

It can be written as a sum of positive squares in 6 ways, for example, as 131921626089796 + 29633586618276 = 11485714^2 + 5443674^2 .

It is a super-2 number, since 2×161555212708072² (a number of 29 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161555212708079) 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 11 ways as a sum of consecutive naturals, for example, 684725322 + ... + 684961222.

Almost surely, 2^{161555212708072} is an apocalyptic number.

It is an amenable number.

161555212708072 is a deficient number, since it is larger than the sum of its proper divisors (143656212662948).

161555212708072 is a wasteful number, since it uses less digits than its factorization.

161555212708072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240742 (or 240601 counting only the distinct ones).

The product of its (nonzero) digits is 2352000, while the sum is 52.

The spelling of 161555212708072 in words is "one hundred sixty-one trillion, five hundred fifty-five billion, two hundred twelve million, seven hundred eight thousand, seventy-two".